how to make your drawing apps for very beginner android

 so created this app and published this on play store and when i created this app i didn't use much knowledge, its like total beginner stuff .

but before sharing this is not at all good approach for making app. and why we should use recycler View .

so here is the screen shots :

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <LinearLayout
                android:id="@+id/banner_container"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_alignParentBottom="true"
                android:orientation="vertical"
                app:layout_constraintBottom_toBottomOf="parent"
                />
            <TextView
                android:id="@+id/textView1"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="1.Draw Angel Fish in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton1"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="angelFish"
                app:srcCompat="@drawable/angelfish" />

            <TextView
                android:id="@+id/textView2"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="2.Draw Angler Fish in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton2"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="anglerFish"
                app:srcCompat="@drawable/anglerfish" />

            <com.google.android.gms.ads.AdView
                xmlns:ads="http://schemas.android.com/apk/res-auto"
                android:id="@+id/adView1"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_centerHorizontal="true"
                android:layout_alignParentBottom="true"
                ads:adSize="BANNER"
                ads:adUnitId="ca-app-pub-8494578888352473/8412491969">
            </com.google.android.gms.ads.AdView>
            <TextView
                android:id="@+id/textView3"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="3.Draw Ant in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton3"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="ant"
                android:src="@drawable/ant" />

            <TextView
                android:id="@+id/textView4"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="4.Draw AntEater  in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton4"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="antEater"
                android:src="@drawable/anteater" />

            <TextView
                android:id="@+id/textView5"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="5.Draw Armdillo in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton5"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="armdillo"
                android:src="@drawable/armdillo" />

            <TextView
                android:id="@+id/textView6"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="6.Draw Baboon in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton6"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="baboon"
                android:src="@drawable/baboon" />

            <TextView
                android:id="@+id/textView7"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="7.Draw Bat in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton7"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="bat"
                android:src="@drawable/bat" />

            <TextView
                android:id="@+id/textView8"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="8.Draw Bear in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton8"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="bear"
                android:src="@drawable/bhaalu" />

            <TextView
                android:id="@+id/textView9"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="9.Draw Beaver in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton9"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="beaver"
                android:src="@drawable/beaver" />

            <TextView
                android:id="@+id/textView10"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="10.Draw Bee in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton10"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="bee"
                android:src="@drawable/bee" />

            <TextView
                android:id="@+id/textView11"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="11.Draw Blue whale in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton11"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:onClick="blueWhale"
                android:background="#FFFFFF"
                android:src="@drawable/whale" />

            <TextView
                android:id="@+id/textView12"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="12.Draw buffalo in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton12"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="buffalo"
                android:src="@drawable/buffalo" />

            <TextView
                android:id="@+id/textView13"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="13.Draw camel in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton13"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="camel"
                android:src="@drawable/camel" />

            <TextView
                android:id="@+id/textView14"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="14.Draw Cat in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton14"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="cat"
                android:src="@drawable/cat" />

            <TextView
                android:id="@+id/textView15"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="15.Draw chamelian in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton15"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="chameleon"
                android:src="@drawable/chameleon" />

            <TextView
                android:id="@+id/textView16"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="16.Draw Cheetah in 7 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton16"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="cheetah"
                android:src="@drawable/cheetah" />

            <TextView
                android:id="@+id/textView17"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="17.Draw chicken in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton17"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="chicken"
                android:src="@drawable/chicken" />

            <TextView
                android:id="@+id/textView18"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="18.Draw Chimpanzee in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton18"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="chimpanzee"
                android:src="@drawable/chimpanzee" />

            <TextView
                android:id="@+id/textView19"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="19.Draw Cobra in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton19"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="cobra"
                android:src="@drawable/cobra" />

            <TextView
                android:id="@+id/textView20"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="20.Draw Cow in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton20"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="cow"
                android:src="@drawable/cow" />

            <TextView
                android:id="@+id/textView21"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="21.Draw Crab in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton21"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="crab"
                android:src="@drawable/crab" />

            <TextView
                android:id="@+id/textView22"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="22.Draw Crocodile in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton22"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="crocodile"
                android:src="@drawable/crocodile" />

            <TextView
                android:id="@+id/textView23"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="23.Draw Dog in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton23"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="dog"
                android:src="@drawable/dog" />

            <TextView
                android:id="@+id/textView24"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="24.Draw Dolphin in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton24"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="dolphin"
                android:src="@drawable/dolphin" />

            <TextView
                android:id="@+id/textView25"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="25.Draw Donkey in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton25"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="donkey"
                android:src="@drawable/donkey" />

            <TextView
                android:id="@+id/textView26"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="26.Draw Dragonfly in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton26"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="dragonfly"
                android:src="@drawable/dragon_fly" />

            <TextView
                android:id="@+id/textView27"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="27.Draw Duck in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton27"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="duck"
                android:src="@drawable/duck" />

            <TextView
                android:id="@+id/textView28"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="28.Draw Eagle in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton28"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="eagle"
                android:src="@drawable/eagle" />

            <TextView
                android:id="@+id/textView29"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="29.Draw Elephant in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton29"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="elephant"
                android:src="@drawable/elephant" />

            <TextView
                android:id="@+id/textView30"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="30.Draw Fish in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton30"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="fish"
                android:src="@drawable/fish" />

            <TextView
                android:id="@+id/textView31"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="31.Draw Flamingo in 7 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton31"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="flamingo"
                android:src="@drawable/flamingo" />

            <TextView
                android:id="@+id/textView32"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="32.Draw Fly in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton32"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="fly"
                android:src="@drawable/fly" />


            <TextView
                android:id="@+id/textView33"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="33.Draw frog in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton33"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="frog"
                android:src="@drawable/frog" />


            <TextView
                android:id="@+id/textView34"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="34.Draw giraffe in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton34"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="giraffe"
                android:src="@drawable/giraffe" />

            <TextView
                android:id="@+id/textView35"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="35.Draw Goat in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton35"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="goat"
                android:src="@drawable/goat" />

            <TextView
                android:id="@+id/textView36"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="36.Draw Goose in 7 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton36"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="goose"
                android:src="@drawable/goose" />

            <TextView
                android:id="@+id/textView37"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="37.Draw Gorilla in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton37"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="gorilla"
                android:src="@drawable/gorilla" />

            <TextView
                android:id="@+id/textView38"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="38.Draw Grasshopper in 9 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton38"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="grasshopper"
                android:src="@drawable/grasshopper" />

            <TextView
                android:id="@+id/textView39"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="39.Draw Shark in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton39"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="shark"
                android:src="@drawable/shark" />

            <TextView
                android:id="@+id/textView40"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="40.Draw Hippo in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton40"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="hippo"
                android:src="@drawable/hippo" />

            <TextView
                android:id="@+id/textView41"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="41.Draw Horse in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton41"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="horse"
                android:src="@drawable/horse" />

            <TextView
                android:id="@+id/textView42"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="42.Draw Hummingbird in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton42"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="hummingbird"
                android:src="@drawable/hummingbird" />

            <TextView
                android:id="@+id/textView43"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="43.Draw Jellyfish in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton43"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="jellyfish"
                android:src="@drawable/jellyfish" />

            <TextView
                android:id="@+id/textView44"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="44.Draw Kangaroo in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton44"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="kangaroo"
                android:src="@drawable/kangaroo" />

            <TextView
                android:id="@+id/textView45"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="45.Draw Killer Whale in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton45"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="killerwhale"
                android:src="@drawable/killerwhale" />

            <TextView
                android:id="@+id/textView46"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="46.Draw Koala Whale in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton46"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="koala"
                android:src="@drawable/koala" />

            <TextView
                android:id="@+id/textView47"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="47.Draw Komodo Dragon in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton47"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="dragon"
                android:src="@drawable/dragon" />

            <TextView
                android:id="@+id/textView48"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="48.Draw LadyBug in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton48"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="ladybug"
                android:src="@drawable/ladybug" />

            <TextView
                android:id="@+id/textView49"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="49.Draw Lion in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton49"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="lion"
                android:src="@drawable/lion" />

            <TextView
                android:id="@+id/textView50"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="50.Draw Lobster in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton50"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="lobster"
                android:src="@drawable/lobster" />

            <TextView
                android:id="@+id/textView51"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="51.Draw Manta Ray in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton51"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="mantaray"
                android:src="@drawable/mantaray" />

            <TextView
                android:id="@+id/textView52"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="52.Draw Mole in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton52"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="mole"
                android:src="@drawable/mole" />

            <TextView
                android:id="@+id/textView53"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="53.Draw Monkey in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton53"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="monkey"
                android:src="@drawable/monkey" />

            <TextView
                android:id="@+id/textView54"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="54.Draw Moose in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton54"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="moose"
                android:src="@drawable/moose" />

            <TextView
                android:id="@+id/textView55"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="55.Draw Mountain Goat in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton55"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="mountaingoat"
                android:src="@drawable/mountaingoat" />

            <TextView
                android:id="@+id/textView56"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="56.Draw Mouse in 7 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton56"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="mouse"
                android:src="@drawable/mouse" />

            <TextView
                android:id="@+id/textView57"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="57.Draw Octopus in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton57"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="octopus"
                android:src="@drawable/octopus" />

            <TextView
                android:id="@+id/textView58"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="58.Draw Penguin in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton58"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#000000"
                android:onClick="penguin"
                android:src="@drawable/penguin" />

            <TextView
                android:id="@+id/textView59"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="59.Draw Spider in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton59"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="spider"
                android:src="@drawable/spider" />

            <TextView
                android:id="@+id/textView60"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="60.Draw Tiger in 6 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton60"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="tiger"
                android:src="@drawable/tiger" />

            <TextView
                android:id="@+id/textView61"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#0C0B0E"
                android:text="61.Draw Wolf in 8 steps"
                android:textColor="#F9F8FA"
                android:textSize="20dp" />

            <ImageButton
                android:id="@+id/imageButton61"
                android:layout_width="match_parent"
                android:layout_height="197dp"
                android:background="#FFFFFF"
                android:onClick="wolf"
                android:src="@drawable/wolf" />


        </LinearLayout>
    </ScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.java

package com.maktech.howtodraw;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.LinearLayout;


import com.facebook.ads.AdSize;
import com.facebook.ads.AudienceNetworkAds;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.ads.MobileAds;
import com.google.android.gms.ads.initialization.InitializationStatus;
import com.google.android.gms.ads.initialization.OnInitializationCompleteListener;

public class MainActivity extends AppCompatActivity {
    private com.facebook.ads.AdView adView;
    private AdView mAdView,madView1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        MobileAds.initialize(this, new OnInitializationCompleteListener() {
            @Override
            public void onInitializationComplete(InitializationStatus initializationStatus) {
            }
        });


        madView1=findViewById(R.id.adView1);
        AdRequest adRequest1=new AdRequest.Builder().build();
        madView1.loadAd((adRequest1));

        //facebook ads
        AudienceNetworkAds.initialize(this);
        adView = new com.facebook.ads.AdView(this, "550981095851123_550983852517514", AdSize.BANNER_HEIGHT_50);
        LinearLayout adContainer = (LinearLayout) findViewById(R.id.banner_container);
        adContainer.addView(adView);
        adView.loadAd();


    }


    protected void onDestroy() {
        if (adView != null) {
            adView.destroy();
        }
        super.onDestroy();
    }


    public void angelFish(View view){
            Intent af=new Intent(this,AngelFishActivity.class);
            startActivity(af);
    }
    public void anglerFish(View view){
        Intent af=new Intent(this,AnglerFishActivity.class);
        startActivity(af);
    }
    public void ant(View view){
        Intent af=new Intent(this,AntActivity.class);
        startActivity(af);
    }
    public void antEater(View view){
        Intent ae=new Intent(this,AntEaterActivity.class);
        startActivity(ae);
    }
    public void armdillo(View view){
        Intent ad=new Intent(this,ArmdilloActivity.class);
        startActivity(ad);
    }
    public void baboon(View view){
        Intent b=new Intent(this,BaboonActivity.class);
        startActivity(b);

    }
    public void bat(View view){
        Intent a=new Intent(this,BatActivity.class);
        startActivity(a);
    }
    public void bear(View view){
        Intent a=new Intent(this,BearActivity.class);
        startActivity(a);
    }
    public void beaver(View view){
        Intent a=new Intent(this,BeaverActivity.class);
        startActivity(a);
    }
    public void bee(View view){
        Intent a=new Intent(this,BeeActivity.class);
        startActivity(a);
    }
    public void blueWhale(View view){
        Intent a=new Intent(this,BlueWhaleActivity.class);
        startActivity(a);
    }
    public void buffalo(View view){
        Intent a=new Intent(this,BuffaloActivity.class);
        startActivity(a);
    }

    public void camel(View view){
        Intent a=new Intent(this,CamelActivity.class);
        startActivity(a);
    }
    public void cat(View view){
        Intent a=new Intent(this,CatActivity.class);
        startActivity(a);
    }
    public void chameleon(View view){
        Intent a=new Intent(this,ChameleonActivity.class);
        startActivity(a);
    }
    public void cheetah(View view){
        Intent a=new Intent(this,CheetahActivity.class);
        startActivity(a);
    }
    public void chicken(View view){
        Intent a=new Intent(this,ChickenActivity.class);
        startActivity(a);
    }
    public void chimpanzee(View view){
        Intent a=new Intent(this,ChimpanzeeActivity.class);
        startActivity(a);
    }
    public void cobra(View view){
        Intent a=new Intent(this,CobraActivity.class);
        startActivity(a);
    }
    public void cow(View view){
        Intent a=new Intent(this,CowActivity.class);
        startActivity(a);
    }
    public void crab(View view){
        Intent a=new Intent(this,CrabActivity.class);
        startActivity(a);
    }public void crocodile(View view){
        Intent a=new Intent(this,CrocodileActivity.class);
        startActivity(a);
    }
    public void dog(View view){
        Intent a=new Intent(this,DogActivity.class);
        startActivity(a);
    }
    public void dolphin(View view){
        Intent a=new Intent(this,DolphinActivity.class);
        startActivity(a);
    }public void donkey(View view){
        Intent a=new Intent(this,DonkeyActivity.class);
        startActivity(a);
    }public void dragonfly(View view){
        Intent a=new Intent(this,DragonFlyActivity.class);
        startActivity(a);
    }public void duck(View view){
        Intent a=new Intent(this,DuckActivity.class);
        startActivity(a);
    }public void eagle(View view){
        Intent a=new Intent(this,EagleActivity.class);
        startActivity(a);
    }public void elephant(View view){
        Intent a=new Intent(this,ElephantActivity.class);
        startActivity(a);
    }public void fish(View view){
        Intent a=new Intent(this,FishActivity.class);
        startActivity(a);
    }public void flamingo(View view){
        Intent a=new Intent(this,FlamingoActivity.class);
        startActivity(a);
    }public void fly(View view){
        Intent a=new Intent(this,FlyActivity.class);
        startActivity(a);
    }public void frog(View view){
        Intent a=new Intent(this,FrogActivity.class);
        startActivity(a);
    }public void giraffe(View view){
        Intent a=new Intent(this,GiraffeActivity.class);
        startActivity(a);
    }public void goat(View view){
        Intent a=new Intent(this,GoatActivity.class);
        startActivity(a);
    }public void goose(View view){
        Intent a=new Intent(this,GooseActivity.class);
        startActivity(a);
    }public void gorilla(View view){
        Intent a=new Intent(this,GorillaActivity.class);
        startActivity(a);
    }public void grasshopper(View view){
        Intent a=new Intent(this,GrassHopperActivity.class);
        startActivity(a);
    }
    public void shark(View view){
        Intent a=new Intent(this,SharkActivity.class);
        startActivity(a);
    }
    public void hippo(View view){
        Intent a=new Intent(this,HippoActivity.class);
        startActivity(a);
    }
    public void horse(View view){
        Intent a=new Intent(this,HorseActivity.class);
        startActivity(a);
    }
    public void hummingbird(View view){
        Intent a=new Intent(this,HummingBirdActivity.class);
        startActivity(a);
    }
    public void jellyfish(View view){
        Intent a=new Intent(this,JellyFishActivity.class);
        startActivity(a);
    }
    public void kangaroo(View view){
        Intent a=new Intent(this,KangarooActivity.class);
        startActivity(a);
    }
    public void killerwhale(View view){
        Intent a=new Intent(this,KillerWhaleActivity.class);
        startActivity(a);
    }
    public void koala(View view){
        Intent a=new Intent(this,KoalaActivity.class);
        startActivity(a);
    }
    public void dragon(View view){
        Intent a=new Intent(this,DragonActivity.class);
        startActivity(a);
    }
    public void ladybug(View view){
        Intent a=new Intent(this,LadyBugActivity.class);
        startActivity(a);
    }
    public void lion(View view){
        Intent a=new Intent(this,LionActivity.class);
        startActivity(a);
    }
    public void lobster(View view){
        Intent a=new Intent(this,LobsterActivity.class);
        startActivity(a);
    }
    public void mantaray(View view){
        Intent a=new Intent(this,MantarayActivity.class);
        startActivity(a);
    }
    public void mole(View view){
        Intent a=new Intent(this,MoleActivity.class);
        startActivity(a);
    }
    public void monkey(View view){
        Intent a=new Intent(this,MonkeyActivity.class);
        startActivity(a);
    }public void moose(View view){
        Intent a=new Intent(this,MooseActivity.class);
        startActivity(a);
    }public void mountaingoat(View view){
        Intent a=new Intent(this,MountainGoatActivity.class);
        startActivity(a);
    }
    public void mouse(View view){
        Intent a=new Intent(this,MouseActivity.class);
        startActivity(a);
    }
    public void octopus(View view){
        Intent a=new Intent(this,OctopusActivity.class);
        startActivity(a);
    }
    public void penguin(View view){
        Intent a=new Intent(this,PenguinActivity.class);
        startActivity(a);
    }
    public void spider(View view){
        Intent a=new Intent(this,SpiderActivity.class);
        startActivity(a);
    }
    public void tiger(View view){
        Intent a=new Intent(this,TigerActivity.class);
        startActivity(a);
    }
    public void wolf(View view){
        Intent a=new Intent(this,WolfActivity.class);
        startActivity(a);
    }
}

activity_angel.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".AngelFishActivity">
    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical" >
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:src="@drawable/angelfish01"

                />
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:src="@drawable/angelfish02"
                android:layout_marginLeft="-89dp"
                />
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:src="@drawable/angelfish03"
                android:layout_marginLeft="-149dp"
                />
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:src="@drawable/angelfish04"
                android:layout_marginLeft="-100dp"
                />
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:src="@drawable/angelfish05"
                android:layout_marginLeft="-100dp"
                />
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:src="@drawable/angelfish06"

                />

        </LinearLayout>
    </ScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>

AngelActivity.java

package com.maktech.howtodraw;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.Handler;


import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.InterstitialAd;
public class AngelFishActivity extends AppCompatActivity {
    private InterstitialAd mInterstitialAd;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_angel_fish);

        mInterstitialAd = new InterstitialAd(this);
        mInterstitialAd.setAdUnitId("ca-app-pub-8494578888352473/6356603441");

        mInterstitialAd.loadAd(new AdRequest.Builder().build());

        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                mInterstitialAd.show();
            }
        }, 5000);

    }
}

repeat this for  all activity and xmls , somple but how it become so hactic