Well, there's a couple of hopeful things in here (welcome, BTW!).
The main one being that HE brought up the issue of being concerned about his own drinking, and confiding that to you, and showing some willingness to get help. Those are BIG positives. It's the people who look for help only to get a spouse or parent off his or her back that are lousy risks.
He may not recover right away, and there may be some slips and he might not go to AA right away, preferring to try to quit on his own, first. None of those things have to be considered terribly alarming. The point is that HE knows he has a problem and wants to deal with it.
I wouldn't worry too much about his recovery efforts causing any huge problems with your schooling. If his drinking hasn't been causing huge problems, it's unlikely that he is going to suddenly go to pieces because he is in recovery. Sometimes there's some irritability at first, and he may have to be off attending meetings a lot in the beginning. But it's a small price to pay if he gets sober before you have a huge drinking problem to live with.