How can a 14 year old boy that needs to lose some weight lose weight fast? -

stop eating junk food, stop drinking sodas, and start moving. walk briskly every day, at least half an hour, or run if you can.

Go for some short runs/walks and build it up.Play more sport (maybe join club).Eat less fats and try more healthy stuff... salad, pasta fruits etc.It is a slow process but keep it up and you will loose weight.But your 14 so dont worry to much about loosing weight cause you will grow it off also.