I Definitely agree with what
@Manydogs said.
Since he isn’t neutered and he has been allowed to be rude and behave the way he has and no manners, I wouldn’t expect his behaviour to change immediately as for the marking and dominance (if he does), cause some of those habits some dogs are used to being allowed to do those things and their behaviour takes longer to improve.
Definitely do NOT let him but you and act like this, he will only get worse if boundaries are not set soon.
Be consistent and patient when dealing with him, praise when he is good, pet him and play when he is in good behaviour. Definitely don’t recommend playing when he is being rude and not respectful to you.
I also agree with the crate, even if he isn’t crate trained, the crate is one of the best things, they know it’s a safe space for them and not a punishment, and they can go in and out and if you go out you can put him it there so he doesn’t get into anything.
But for you the main reason for the crate is put him in there to calm down. Or if he is being rude to you and biting, put him in the crate to settle.
If he barks or whines do NOT let him out or give affection(that’s rewarding bad behaviour),, he will test you to see if you will give in and let him out when he wants. He needs to calm down and also learn boundaries and patience.
If he is anything but calm in the crate, ignore it(I know easier said than done sometimes).
When he is quiet and calm, reward and tell him he is a good boy give treats and play/praise when you let him out if crate. I’m not saying to have him in the crate lots, just when he is in the bad behaviour times.
He will learn, it will take time but these dogs are extremely smart and will figure it out. Eventually you shouldn’t need to put him In the crate, he should be able to listen to the calm down command or be able to listen and respect you without biting or being rude.
When he bites, say in a firm different tone “No biting” .
Sounds like he got away with a lot at the other place or he had no rules/limits or the people weren’t good to him. But he will learn with you what is allowed and what is not.
I know this is also hard sometimes, but you need to stay calm and confident cause if your stressed, frustrated, upset etc. he will pick up on your energy and reflect it with bad behaviour.
It may help to work on commands with him too and give treats/affection when he listens.
You could for example start by practicing ‘sit’ or ‘lay down’ or ‘stay’
When he listens to you, praise, reward with high value treats and give affection. Say ‘yes good sit’ for example.
He will learn he has to listen to you and YOU are in charge NOT him.
Then when he does well with this listening to commands, when he is rude behaviour or about to get into biting mode, ask him to Sit or lay down, then your redirecting his mind, he will know that’s not allowed to bite and be rude but your also asking him to do something. Or redirect him to get you a toy to throw for him BEFORE he starts biting, it’s a matter of knowing when he is gonna start the biting, so if you think he is gonna start to misbehave, ask him to do something to get his mind off of wanting to be rude.
