2old2wade

Friends, New to boating and fishing. Just bought a new to me 2005 panfish 16 stick steer. No manual or instructions. It has a 25hp 2 stroke, livewell, and fishfinder. I need the experts to tell me what the 3 holes in the stern are and if all of them need to be plugged before entering the water? I figure that one is the main boat drain(large diameter aluminum), and the other 2 may be for the live well system. I appreciate everyones help. I am taking a boater safety course, getting the required gear together, and hope to get the kids on the fish in a few days. Thanks again.