Look for a whey protein for post workout drinks. you want one with low/no fat low/no sugars and a reputable company. There are other types of protein that digest slower or for people who can't tolerate whey but that should be fine as a starter.
I take centrum. People also like mega man. that's all you'll need there. People will take
Flax oil, Omega 3's and Heart/liver/prostate supps too.
Keep it simple right now and don't worry about taking 20 pills a day. Get a Multi-V, Whey protein and learn to eat healthy.