I need help for my weight...please I'm desperate?

OK, so I'm 15 years old, 6'1-6'2 and 230 pounds, I'm big boned, and I've been working out since I was 12, lifting weights and stuff. So its been almost a year that I have been in kickboxing/boxing. One of the guys in my gym weighed 230 and he lost 50 pounds by just training and eating healthy. So that's what I need to do now. I know summer just started so my goal is to be 210-200 by the end of summer. I've been on a diet for almost 2 weeks now which is just eating ALOT of chicken, like turkey , chicken , red meat, steak, and bacon (bacon only in the morning). no soda, chips, etc. I also drink 5-7L of water a day. So, I was wondering if I can lose weight by training 4 days a week, Mon-Thurs, and hitting the gym before my cles start so I exercise double in one day and hitting the gyms on the weekends, so pretty much taking Friday off. I've already lost 3 lbs in a week but I need to hit my goal, so can someone please answer my questions? Like I said before, I'm desperate. Thanks.