It's true if you do weight at 16 years old you will not grow ?

Bone growth: Not necessarily.If bones have not fused you may still be able to grow without difficulty.

Use a trainer: Weightlifting like many sports activities can be beneficial if done right & can produce significant injury if done wrong. Any novice should be supervised by a trained professional, preferably one certified in the area.Early training focuses on technique & low intensity weights. Powerlifting & bodybuilding are not recommended until the kid reaches skeletal maturity (final height, b.o., shaves).