How can I lose about 100 pounds?

I'm a 15 year old guy and weigh about 230 lbs, and am maybe 5' 9".. I've been working out maybe 5-6 days a week for like the past 2 months but haven't been loosing any weight. What can I do to start to lose weight, about 100 pounds. And do it as fast as possible without it being unhealthy. I'm always getting exercise or working out so i got that covered. But I can't exactly eat foods that are that healthy because I just eat whatever my dad makes for dinner, and usually cereal or a pop-tart for breakfast. School starts in about another month so I'll be able to eat better **** then I usually do for lunch. Please help because I really want to lose weight asap, especially since ill be gettin fu*kin jacked from workin out.