All dogs, no matter what size or age, need, desire and require training. Without it they can become confused, stressed, and destructive. They can become difficult to manage.
The only solution to these problems is learning to communicate with your dog, to give them clear direction. I have found over the years that the best way to accomplish this, is through consistent private one-on-one weekly training. Structured training that includes dog behavior modification, dog obedience training, dog owner communication, and puppy socialization training, help dogs and puppies adapt to their environment in a healthy way.