3 questions, 1: what is the benifit of yoga 2: where are some good yoga sites that can start me off. 3rd in Q?

3 questions, 1: what is the benifit of yoga (what kind of excersice would it give me) 2: where are some good yoga sites that can start me off (giving me some basic yoga tips and junk). and 3: i need some good advice on how to stop eating fatty foods and how to stop eating after meals…stuff like that.
PS. if you just want to answer one question then go ahead and say which one u answer.