I wanna lose about 50 pounds in like, 5 months?

Now do I really have to go on a certain diet to do this, im 16. I tried the lo carb diet for a day and it looks impossible, everything has carbs in it, even soup. So im wondering if i can just, you know, make a lifetime eating change (my only problem eating is eating late since i stay up a lot playing xbox with my friends, i tend to munch on some snacks like chips or something) but i plan on stopping that. As for my excersise, i play so much basketball, it should be illegal, im starting p90x, and i longboard. i dont drink soda, i drink a lot of water and diet nestea iced tea ( so good ). With this regular eating less diet and my exercise, can i achieve this, like is it possible, or do i need to go on some special diet. keep in mind i cant really control what dinners i have, my mom usually cooks a lot of rice with like spinich and stuff. chicken usually. but can i get this weight loss with just eating less and my exercise. Thanks in advance.