If you have a friend:
* "Mi amigo/amiga se llama [nombre]." (My friend is named [name].)
If you don't have a friend:
* "No tengo amigos/amigas." (I don't have any friends.)
* "No tengo un amigo/amiga." (I don't have a friend.)
* "Todavía no tengo un amigo/amiga." (I don't have a friend yet.)
Remember to replace "[nombre]" with the actual name of your friend.