It sounds like there’s some anxiety influencing his behavior. He’s trying to grab as much control as possible, because he feels so lost without any. Make sense?
I’ve taught my son some social rules. He’s a real stickler for following rules and a very concrete thinker, so this works well for him. For instance, when you meet someone new, you say, “Nice to meet you, my name is L, what is your name?” When you have a friend over, they always get to choose the first activity because they’re your guest. Things like that have helped a great deal.
Time blindness can also be a factor here. My son dominated the play with friends because he felt like he never got his share of the time, when it was just the opposite. We used a timer and each person chose what to do and got 30 minutes on the timer, then you switched. He couldn’t argue that he didn’t get equal say or that it wasn’t fair, due to his poor sense of time. Of course, that was when he was younger (he’s 15 now).
Lastly, kids with ADHD often have trouble seeing the big picture and seeing more than one way of doing something. All they can see is the thought they’re having. This looks like they’re bossy and domineering on the surface, but it’s just the narrow vision of their brain.
There are some good tips in this article to help social relationships:
ADDitude Community Moderator, Parenting ADHD Trainer & Author, Mom to teen w/ ADHD, LDs, and autism