The Color of the Pomegranates. My film school buddies always recommended it. I fell asleep in two attempts to watch it. I finally finished it, but only because I was doing my taxes and that was more entertaining.
It sounds more complex than just ADHD (could be bipolar, borderline, schizophrenia, etc.). He will need to adjust his goals and try different physical activities. He will need to have a medical regimen and follow it to the t.
As a family, you will need a support circle. You will burn out very fast, so family therapy is key.
Neopets storylines, like the Fall of Faeryland in which players around the world had to fight to defeat an enemy. And the world map grew with every storyline so it didn’t feel stale.