How do you reply to cómo te llamas?

it is asking your name, so you can reply with one of three things:

1. just your name

2. by saying "Me llamo ___" (I am called ___)

3. by saying "Soy ___" (I am ____)

Example.

Person A: ¿Cómo te llamas?

Person B: Me llamo [Name].

Replace the Brackets with your name