Hi my name is Jason,&im 15 about to turn 16.When I was a kid I use to make myself faint by cutting ogg my air circulation(now I know that it kills brain cells).I use to do it a lot I would say 65 times in my whole life mabe 50 flat.Do you think its going to effect me later in life?Anyway eversince then I want my body to be healthy and my brain more importantly.what happens when a lot of your brain cells die?is there a way to make to make my brain healthier?get back to me.. peace

Your brain can not replace dead braincells and reconnect them in such a way that neuron networking (i.e. "thinking") reoccures.
What is gone, is gone forever.

Luckily your brain has a gigantic oversupply of braincells, and is capable of "rewiring" some of these cells into action. However, the earlier that happens, the more effective that is.

Seeing your spelling it may well be that you have passed that period already... ;)