Para has two meanings.
(1) to (a place)
You can use either a, or para to express to. In general, using para implies that you are going to somewhere in order to be there a while. Usually that’s to your home, to work etc. But don’t get hung up on this – time is relative 😉
to ➜ Eu vou para o brasil. (I'm going to Brazil.)
to ➜ Você vai para a praia? (Are you going to the beach?)
(2) in order to
in order to ➜ Eu estou aqui para estudar. (I'm here to study.)
in order to ➜ Trabalho para ganhar dinheiro. (I work to earn money.)