Yea, that's some good advice to shed the weight. Cardio and full body stuff will do that quickly. Later one when you've lost the fat that you want to lose I'd look into a bulking routine, but for now that's perfect. Pull downs are your best alternative to pullups. Weighted pull downs like this guy is doing: Either that or assisted pullups if you go to a gym. You can set the weight which basically assists you so that you're only lifting your weight minus the weight you set. Also, throw pushups into that set of excercises if you want it to be more effective.