A dog crate and obedience training can work wonders.

He won't want to go potty in the crate so it will teach him to hold it and he can't chew up things that aren't his. When you find him chewing the wrong things, take them away and give him a chewy or his own toy. Give him lots of exercise so that he gets tired and won't be so destructive (he is half terrier). "A tired puppy is a happy puppy."
Get him on a regular routine: potty when he wakes up in the morning, then breakfast, 20 minutes later (give or take) go potty again, then straight to the crate when you leave the house. Retpeat this process when you come home in the evening. Praise him like crazy when he goes potty outside so that he knows that's where he's supposed to go. To begin with you may have to crate him at night also so he can't destroy things while you're sleeping.
Sign him up for training classes ASAP. This will teach him his basic manners and it helps the two of you bond. Find a trainer that is going to teach you how to teach him, beware: don't leave him at a training facility, you never know what's going on.
If he's not already neutered, having that done will help in many ways. From the sounds of this boy, he must have been an outside dog, so it's going to take some time and patience to get him to understand the rules of your house. Hope this helps.