It's not so hard as you think to get into USP. Actually, it's kinda easy if your family paid you a good education by brazilian terms, which basically means you studied in ETAPA or Objetivo and can't reason about more important matters but have over 9000 test exercises under your belt.

I advise you to not give a shit about it because you can learn way more at home, unless you want a degree. If you do want that piece of paper with their name, study and get inside.

99,9999% of research there is shit, if you are serious about it, try to find a way to move and study abroad(depends highly on your family's social status, hehe).