Having issues training my puppy?

First off i have trained about 10 dogs including housebreaking, and basic obedience but now I'm having troubles...about a month ago me and my bf got a 9 month old Shepard mix puppy from a shelter, and he has been hard trying to train him. We walk him 3 times a day and take him out whenever he looks like hes about to use the restroom, when he uses the restroom inside he get reprimanded and set outside, when he uses the restroom outside he gets praised. I can take him outside make sure he does his business and the minute we walk in he will squat and pee on the floor. He started a new habit of chewing furniture and he has chew toys and we give him rawhides, and when we catch him we reprimand him. We don't crate train him cause someone is always here plus we tried putting him in the master bathroom and he just broke through the door. I'm at a loss and I need to get him controllable and fast.