¿Cómo se llama ese muchacho?
You say, "gemelos."
You can say los chicos for the boys, and las chicas for the girls.
it is a boys name
Yes, Miguel is a Spanish name. It is a common given name for boys in Spanish-speaking countries.
Nothing, that's in English. But if you meant to say HOW to say teenage boys, then its "adolescentes"
hola chicos
Odio los chicos.
acelerado for boys and acelerada for girls
me gustan los chicos
Nuestros muchachos. (Chicos, niños.)
girls, debriefia and boys, debriefio
Girl who are friends are amigas in spanish. Further boys are amigos