How to make this CardView with a circle containing a letter

I want that CardView, contains Name and First letter of the name in the circle. Just like the contact on our phone.

You can just use the Material Components Library:

<androidx.cardview.widget.CardView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    ..>

   <TextView
       android:id="@+id/textview"
       android:layout_width="64dp"
       android:layout_height="64dp"
       android:gravity="center"
       android:textSize="30sp"
       android:text="D"
       />

</androidx.cardview.widget.CardView>

Then in your code you can apply a MaterialShapeDrawable:

    TextView textView = findViewById(R.id.textview);
    ShapeAppearanceModel shapeAppearanceModel = new ShapeAppearanceModel()
            .toBuilder()
            .setAllCorners(new RoundedCornerTreatment()).setAllCornerSizes(new RelativeCornerSize(0.5f))
            .build();
    MaterialShapeDrawable shapeDrawable = new MaterialShapeDrawable(shapeAppearanceModel);
    shapeDrawable.setFillColor(ContextCompat.getColorStateList(this,R.color....));
    ViewCompat.setBackground(textView,shapeDrawable);

The RelativeCornerSize(0.5f) apply rounded corners with size=50%. In this way the view becomes a circle.

Just a note about new RelativeCornerSize(0.5f): It changed in 1.2.0-beta01. Before it was new RelativeCornerSize(50).