you have more friends on facebook than you believe
"Tienes amigos" in English translates to "you have friends."
You have facebook. Written as ¿Tienes facebook? it would be "Do you have facebook?" it could also be a statement to people but most likely in the form of a question. Ex: Tienes facebook? = Do you have facebook?
"You have many best friends."
The phrase "por que tienes en amigos" doesn't make sense in Spanish. It seems like a non-standard or incorrect combination of words. A correct phrase could be "¿Por qué tienes tantos amigos?" which translates to "Why do you have so many friends?"
Crees que = You believe... . / Do you believe... ?
"Primos tienes" means "Do you have cousins?" in Spanish.
to think
"Tienes" means "you have" or "do you have".
si can be "if" or "yes" tienes comes from tener which mean "to have" there it can be either "if you have" or "yes you have/you do have"
"tú crees" translates to "you believe" in English.
"Tienes primos" means "you have cousins" in English.
Cual almuerzo tienes = what lunch do you have?