STEP 1/
Start by creating a folder named assests
then inside that folder create another one named folder
and import your *.ttf
files to that folder
STEP 2/
Now import this before start writing the code given below:
import android.graphics.Typeface;
Now implement the following code to your class:
// Font path
String fontPath = "fonts/Face Your Fears.ttf";
// text view label
TextView txtGhost = (TextView) findViewById(R.id.ghost);
// Loading Font Face
Typeface tf = Typeface.createFromAsset(getAssets(), fontPath);
// Applying font
txtGhost.setTypeface(tf);
I suggest you follow this tutorial right here it will guide step-by-step through using external fonts in Android Studio