I have no idea what I am doing.
Perhaps find a psychiatrist for your son to get an evaluation and to see if he likes the person. Healthgrades rates MDs, so that might be a place to start. Insurance could be a problem, as many don’t take it. In that case, if you have the resources, you’ll have to pay out of pocket.
The reason a psychiatrist is important is because they can prescribe meds, which can be enormously helpful.
If your son does not want see one, then I Am Not Sick, I Don’t Need Help! How to Help Someone Accept Treatment is the go-to book.
Another idea is to also start reading the threads on this forum. Enter some words that pertain to your situation in the search box on the upper right.