In pretty much every thread where someone young, under the age of 17 or 18 asks about training I believe we have always recommended to take it lightly for the time being. Yes intense strength training can stunt growth somewhat or cause injury. There are still ways to go to failure without using weight anywhere near your max rep though. But again don’t be doing too much…at that age you are still growing and who knows how you’ll end up.
I think stress is even a larger enemy
Now this is the most factual quote in the whole thread.