Have you tried giving him a fidget toy whilst he’s sat down, or maybe get him to pass the drinks bottles round as your talking, distraction is the key if he’s taking it in and you still want him around everyone else

My boy has a mild ADHD. He's smart & does all the things you mention. It took me several years to realise this. I don't know if this is of any help for you.

Hi Anthony, your son sounds like a typical 4-5 yr old, with a head full of brilliant ideas they want to express, that at times can be overwhelming and they just want to do stuff. Have you spoken to the coaches, and asked how they feel he's doing. I know from past experience many parents expect their children to 'behave' and sit when asked, listen process and then do. Good luck with that, that's a short journey to pulling year hair out. He has a different learning preference, some like to be shown, visuals, demos, others like to be told, then theirs this who like to do, and experience need to experience the games to understand. I'm sure your coaches are aware of this, but it may be worthwhile mentioned to them that he struggles with the sit down, sit still listen, keeping the info break short and specific to the next learning action and then scaffold these over the session bit by bit may help him. But at the end of the day, the key to working with your players that I have found, is I as the coach need to have a better/more fun idea in my head than he has in his. I'm sure with some patience and support he will come up with strategies as he gains experience that will help with his focus. But there we go again, talking about focus (another adult concept for young players doing what we expect). Young players are sponges, they soak everything in. But, they don't always express that in a way that matches our expectations as adults. I've had  many a session where I come away thinking that was a disaster, they didn't listen they, didn't understand, only to find out some weeks later in a game the very thing that was a 'train wreck' in practice, they can do. Give him your patience and support, let him be 5 or 6yrs, give him praise when he does something and tell him what you liked. At info breaks I invite the players to sit on their ball, that prevents a lot of the behaviours, invite them to look at my visual board, which they have already seen since they arrived, quickly explain how we start the next game and get into it as quickly as I am allowed. Celebrate his difference, being the same as everyone else is, I think overrated. I wish you both well in you shared football journey, you will get there I'm are, though be prepared for a few unscheduled stops and diversions along the way.