Is my lab punishing me?

Question
Hi I have a Black lab a little over three months. I really need help. He is not horrible, but there are a few things about his behaviors that have me concerned
The first thing is that I have him in an area of the house that I can keep an eye of him, but now he is bigger and knocks the gates down when he freaks out when I leave the house. He doesn't chew on anyone else in the house's belongings but mine. Seriously I could put two pairs of shoes on the floor and  he will ruin mine and not touch the other persons. I am working on potty training, but I read this book that says to not scold them when they pee right in front of you. Just clean it up and take them outside. This has turned into a catastrophe, he will go outside and play come back in and pee on the floor and try to go right back out, and if I do try to discipline him he will, walk away after I am done and pee right where I can see him. I really need some help, he has been this way since I got him, and I don't know what else to do.

Answer
I would recommend crate training.  The baby gate is fine when you need to keep him in a confined area when you are home, but when you leave the house, the dog should be in a crate.  I recommend crate training from the MINUTE you get the dog home.  

As far as chewing your things, you will continue to have this problem until the dog is grown.  Crate training and picking your stuff up off the floor and tables will help.  Remember the dog is not a human and doesn't know that it shouldn't be chewing on your things.  It will pick your things because it smells like you and if you are the primary care giver, it will be more attracted to you.  If you find the dog with something inappropriate in it's mouth, correct him and exchange the item for an appropriate doggy toy and PRAISE.  He'll learn Mom is happy when I chew on my bone.  You cannot correct for chewing after the fact.  If you come into a room and the remote control is in pieces, there is nothing you can do.  If you catch him with it in his mouth, THEN you can correct.

As far as potty, corrections for that work the same.  IF you see the dog start to pee/poop in front of you, you should YELL NO NO NO or AH AH AH, and rush to pick the dog up or escort it outside as quickly as humanly possible.  Then when it potties outside, HUGE HUGE praise.  The idea is to interrupt the dog going in the house and get him out quickly.  If the dog potties when you did not see it happen, you can't correct.