It is said "Bienvenido de nuevo"
"Welcome back" in Spanish is "Bienvenido de nuevo".
De nada
the official language in Mexico is spanish. welcome in spanish is bienvenido.
You're welcome handsome in Spanish is three simple words. To say "You're welcome handsome" in the Spanish language would simply be "de nada guapo" and can be easily said.
Bienvenidos de vuelta
Bienvenido a México (if said to one person). Bienvenidos a México (if said to more than one person or to people in general, as on a sign at the border).
In Mexican Spanish, you can say "bienvenido de regreso."
You don't typically have to say anything in response. When someone says some variant of "You're welcome", that pretty much closes out the interaction (since you've already said "thank you").
If you mean You are welcome, it is 'De nada'
"Welcome" in Spanish translates to "bienvenido" for a male or "bienvenida" for a female.
The phrase "Welcome to the States" translated into Spanish is "Bienvenidos a los Estados"
bienvenido/a (adjective) bienvenida (welcome!)