I need all the help I can get

Hi everyone. I have a 5month staffy, I’d be lost without him and I do try to stay calm majority of the time but I swear from the day I got him he thinks I’m some sort of big toy, biting, tugging, you name it he does it.. and don’t get me wrong I don’t mind abit of play time but I literally can’t even fuss him or walk 5 steps without him either biting my trousers, jumping up to bite my pockets or just having the time of his life with my hands. I’ve tried everything, redirecting, walking away.. he’s fine for say 30 seconds and then he’s right back at it. And it’s getting abit much now, is there anything else I can do? I’m also sure he has selective hearing, the amount of times i say ‘no’ ‘off’ ‘down’ is mental🤣 and I do give him a little tap now and again because sometimes he’s a little too aggressive and after a constant 20/30 mins of him biting it does whittle down my patience but a more physical approach doesn’t faze him in the slightest. Anything else I can do without locking him in the kitchen for hours on end

Thank you