You can create an ImageButton in your android activity_main.xml and which image you want to place in your button just paste that image in your drawable folder below is the sample code for your reference.
<ImageButton
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginBottom="49dp"
android:layout_weight="1"
android:onClick="prev"
android:src="@drawable/prev"
/>