Helping your child: prevent and deal with addiction

The course was revealing and inspiring
Infact, I have been a victim of emotional abandonment, and I passed it on to my children, being too strict and always criticizing them
I have decided to be more patient and loving to them
However, the eldest of my children is 21 and I just found out that he has been using cannabis, although he has been seeing a psychiatrist, but now, I know, I need to renew my own mind….
Are there other practical ways, or other ways, I can take