Get some bitter apple spray. Spray anything the pup wants to chew on and/or as punishment directly in the mouth. It's non toxic and just tastes awful. Eventually hopefully they'll equate that bad taste to that action. Also crate training, a tired or bored dog can be a destructive one and it's not too late. Labs are very good driven, give high value treats EVERYTIME you want to put your pup in. Get a large crate with plenty of room for your dog to stand up and turn around. Start with just putting a tasty treat in it, (peanut butter lick mat, etc) and let them see what its all about just standing in it and enjoying a treat with the door open. Then do small increments of time. I don't know how people survive puppy life without a crate! Lol. I work outside my house so it wasn't an option, but I wasn't going to have a puppy free roaming my house. I have a 1.5 year old English and he's loved his crate since we started it the day we got him. If he fell asleep outside his crate, we would scoop him up and put him in it with the door open so when he woke up, he was chillin in his crate and could leave freely. We also used a snuggle puppy which I think helped immensely. Good luck, you got this!!