Im eleven and I weigh 220 pounds im 5-4" and I just want to lose weight shoild I sighn up for a gym?

I'm 12 and 1 I just want to say you naturally BEAUTIFUL. Haha But of course you should eat foods with more nutrients, protein and iron. ALSO Exercise but always balance it out with healthy eating. NEVER EVER diet because the more healthy and often you eat with boost up your metabolism and help get rid of the excess fat you may have. Or it could just still be baby fat which I highly doubt. Good luck hun :) And P.S. To all the jerks don't say shi*t about how she shouldn't be on Yahoo Answers ugh haha srry
Help me with mine plzz: http://answers.yahoo.com/question/index_ylt=AidY29sLcHmzTJz49qFwkb7sy6IX_ylv=3?qid=20120202204141AAlEkGV