The squat is the “king of all exercises”. This would help to reduce
The exercises are:
Sit-ups (most important, try 500 )
Half squats
Bench Curls.
Inverted bench curls.
Laid back press
Normal seat press..
It is true that the growth of height would be stopped if u start doing this so it is better to start going to the gym once your growth is over and if you are sure that you would not grow hence further.