The answer would be vende, meaning sells
It depends if you they like the party’s or not but since s it’s in ellos(them) form it would be this:
no,no les gustan las fiestas
no they do not like party’s ^
si,les gustan los fiestas
yes,they do like party’s ^
Nuevos Amigos because its plural
Mejor amigo? ( best friend? ) it could be but don’t know exactly what you need