In the below example I have created a simple fragment app code. Here, first I have created two new fragment xml layouts and neamed them fragmentone and fragmenttwo then in this I have added TextView and backgraund image. Now In activity_main.xml I have added two button and a fragment layout, in fragment layout I have added package name. Now in next step I have created two new class (FragmentOne and FragementTwo) both class exetend with Fragment class. In MainActivity I have used FragmentTransaction class and getFragmentManager() method. You can see below example code it clearly describe you "How to create fragment In android”.

Step(1)Create a new fragmentone.xml layout-

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@drawable/one">

    <TextView
        android:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:text="Evon"
        android:textStyle="bold" />

</LinearLayout>

Step(2)Create a new fragmenttwo.xml layout-

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@drawable/two">

    <TextView
        android:id="@+id/textView2"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="Ericsson"
        android:textStyle="bold" />

</LinearLayout>

Step(3)activity_main.xml layout-

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    <Button
        android:id="@+id/button1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Fragment No.1"
        android:onClick="selectFrag" />

    <Button
        android:id="@+id/button2"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:onClick="selectFrag"
        android:text="Fragment No.2" />
    <fragment
        android:name="com.tiwari.rajshekhar.fragment.FragmentOne"
        android:id="@+id/fragment_place"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</LinearLayout>

Step(4) Created a new FragmentOne class-

public class FragmentOne extends android.app.Fragment {

        @Override
        public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState){
            return inflater.inflate(R.layout.fragmentone,container,false);
        }
}

Step(5) Created a new FragmentTwo class-

public class FragmentTwo extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState){
        return inflater.inflate(R.layout.fragmenttwo,container,false);
    }
}

Step(6)MainActivity-
 

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }
    public void selectFrag(View view){
        Fragment fr;
        if(view ==findViewById(R.id.button2)){
            fr=new FragmentTwo();
        }else {
            fr = new FragmentOne();
        }
        FragmentManager fm=getFragmentManager();
        FragmentTransaction fragmentTransaction=fm.beginTransaction();
        fragmentTransaction.replace(R.id.fragment_place, fr);
        fragmentTransaction.commit();

    }

}