Hi i have a 10 stone american bully who is absolutely brilliant until i get a visitor. He gets so excited and jumps all over them . When anyone goes to leave the house he does the same and attacks my doors . I just dont know how to calm him or how to handle this problem.  Can anyone give me some tips please

How long have you had him ?

I'd be inclined to get in-person help for this tbh, so they can see body language and establish exactly what's going on.  That's quite extreme behaviour just for a bit of excitement!  You want someone force-free who doesn't talk about dominance and punishment.

In the meantime, Boundary Games would be a great start to help him learn to stay in one place until released.  If you google 'Absolute Dogs Boundary Games', there is a free ebook.

He is my sons dog that i have taken on but ive trained him since he was a pup. I now have him full time as he was distroying my sons flat and he could not have any mates in as the dog just got to high

So you've been training him since he was a puopy, but he's still misbehaving whilst living with you full time.

You definitely need professional help & quickly before someone gets hurt

Yes, I can only reiterate what I said.  You need help in person.  AMBs can be a handful sometimes, usually when they hit teenage months but this is extreme behaviour, whatever age he is.  The boundary games will still be a good start as they teach a dog how to relax in one place, but I don't believe they will be sufficient in this situation.  Something has gone off track somewhere for him to be behaving like this.