Welcome and knowntou are not alone. These behaviours are going to lead to more difficulty for your son as he get older if he does not start to be more compliant with societal rules.
I know how this fe last my Difficult Child is now 18 and does not have his high school diploma and is facing adult criminal charges.
Has your son been assessed for any form of issues or challenges? Does he see a therapist? Do you seek therapy for yourself? This is not an easy situation to manage.
I might suggest if he is not compliant with school rules, is smoking pot and or other drugs and has violent tendacies a job is going to be difficult to find or hold onto.
Setting boundaries and expectations at home is very important. This will need to be done with the support of all parents involved. If he breaks the rules you must be prepared to follow through with consequences.
Ther is a good book that is called Don’t Let Your Children Kill You. It’s worth a read.
You are not alone. This is a very challenging time. Many people here are facing similar struggles.