Is there a way to make it so each team can see a specific portion of the map at the start of the game?
My idea is to have a large mineral/gas cluster in the middle of the map, and all the teams have to fight over the main part, but nobody likes to do anything because they can't see the minerals at the start. Is there a way to fix this?
Fog of war layer. Hold shift to see all players.
Or if you want perma-sight (not just map revealed) use a Map Revealer. Then again, you should already know that.

But I don't. Most everything I know is basic stuff that I have figured out by myself...
Wow I didn't imagine you as a newb,
Just do what that guy above said use fog of war or a map revealer.
I tried that but it didn't last more than a couple seconds (not long enough to get the AI moving...)
To get the Ai to move to somewhere, use one of the Ai scripts and locations.