Basketball the Questions

OK Im a bit of a fan of most sports and this evening have been watching the Duke - UNC game from last Wednesday night and would like to ask a few questions about the game. Firstly appologies on how stupid the questions maybe but I need to get some answers to assist me.

1) What exactly is a Field Goal?
2) What are the rules on players in Collage basketball?
3) How long do players get to stay playing for collage teams?
4) Where do they go after Collage basketball, surely they all dont go to the NBA?
5) Are all home supports like the Duke support? by that I mean colourful and loud.
6) I know why shot fouls go to the free throw line but why do other fouls go there too?

Im sure that I will think of some more in due course however I would like to make the following opservations about the game.

1) The crowd were exceedingly loud and colourful.
2) Although used to ice hockey (my #1 American sport) I found this game exceedingly fast and frantic.
3) Duke seemed to be slow off the staring blocks in the two halfs going down 11 early on in the first and then loosing wha appeared a good in the second and then failing to recover from going down.
4) Dukes #3 Paulus seemed to be everywhere early on making some great plays. I presume he is one tio watch in the future to hit the NBA