My fiancee and I want to get married through the justice of the peace to help speed up his legalization process.

He has a job.
We live together.
He is from mexico, here illegally.
He has never gotten into legal trouble.

Can we legally get married if since he doesn't have a US state drivers license?
If we get legally married what will be the next step to get him legal?
Will they deport him if we go to get married?
Can he attend college with no legal status?
What will him marrying me even do at all?

Sorry to start a new thread on the same thing others are asking generally, but I need answers fast!