Hi everyone... after a bit of a time searching in which forum i can post this questions, I've decided here.. Hope I got it right

I'm new and this.. it may sound a silly question, but, I need to learn.

1) How do I now what am I? (F.O or Captain?) Is there a study orientation to become a FO/Captain by separate? Or it depends on you skill, hours flown, etc..

2) Most flight schools I've seen has an B737 or an A320 flight simulator. How can a pilot become a 747 FO/Captain with just A320, B737 or small aircraft "experience"?

Thanks in advance.