According to the American Heart Association, a male your age should eat about 2200 calories a day if you are not active. If you are moderatly active then eat about 2400 - 2800.

I have been working with a trainer for about three months, and I can tell you that you really need to get some cardio into your daily routine. Use a tredmill or a recumbent bike for a minimum of 20 minutes and work your way up to 60 minutes. You should also add some weight training to your routine every other day.

I know that it is hard to work out by yourself so try and get a friend to do it with you or join a gym, they have trainers that may be able to help you get started.