I really want to start going to gym, I'm 14 years old and I don't do any sports anymore. I used to do swimming twice a week for 4 years straight but 8 months ago I dropped out. Now I've noticed a lot of weight being gained on my stomach which is the worst. Does anyone go gym and how long do you think I'll have to go to get rid of belly fat (it's not that much it's just not flat)?