A Rottweiler – German shepherd mix. I have had him since he was born. I need advice and tips. I am lost.

So, I own a Rottweiler – German shepherd mix. He is just under 4 months. He weighs 31 lbs. He is so stubborn it's unbelievable. He knows commands like 'pad', 'potty', 'sit' and 'get down'. He disobeys on purpose I swear. He looks at me as he does something he knows gets him in trouble. Hes destroyed the corners of wooden furniture. He destroyed books and DVD cases. He side-eyes me right before he does something.

He has ate SO MANY socks. Luckily they didnt cause any problems. And he won't leave people's toes alone. He growls playfully and lunges at feet, and it hurts when he actually succeeds.

He also has an aggression issue. He growls, barks, or tries to snap at you if you get close to his food or a snack (ex: peanut butter, chicken, etc). He also gets randomly 'aggressive' if you pull his collar. Idk how to manage it or fix it. (His bio mother was also food aggressive.)

He is so rotten and knows it. I want to be a good dog owner but it is so hard for me. I have days I think of getting him a different home but I want to bond with him and id hate to get rid of him. But it is hard when every day is mentally taxing and stressful.

I've started walking him for short periods since it has been nice out. I am trying to potty train him and teach some simple commands.

So my questions for advice are:

1. How do I make him stop chewing on literally every surface?
2. How do I get to stop peeing on the carpet?
3. How do I make him not bite limbs or people's body?
4. How do I fix or manage his aggression?
5. How do I train him not to pull/choke himself? Or try to play tug-a-war with it?
6. How do I prevent him from peeing/pooping in his crate?

Please be nice and I'd really appreciate any tips or advice 🙏

[I am a first time puppy owner. I've only owned a cat or been around adult dogs.]

[Edit: We had his mom first (before she was pregnant) then had him and his siblings. The mom and puppies found homes after they could leave. Mama dog was ex bf dog so he took her back after the pups left. We kept this guy]