Depends on the university, the subject and the student. But for most subjects and places it’s a little bit easier for an overseas student paying higher overseas fees to get in than it would be a home student with the same basic ability. Something like medicine is a lot harder, because overseas places are capped.
No guaranteed admission anywhere - there are minimum grade requirements, but you can’t be sure you’ll get an offer based just on stats.
Generally speaking, you’ll need to have at least three AP exams with a decent score to be considered, where possible in subjects related to what you plan to study.
What do you want to study?