The main source of exercise for a young puppy is usually exploring their yard and home. Because they need frequent naps, puppies don't need to be taken on long walks. When walking the main focus should be on learning their walking manners, not going for miles at a time. Playing with toys and chew bones is also a good source of exercise for a young puppy
If you have been doing lots of obedience training, and your dog has been spayed or neutered, now is the time to start heading off to the dog park for a good run and some social time. Dogs love to retrieve balls, but you have to be careful that you don't allow them to become obsessed with the game and frequent stops and starts when running can cause joint damage to a dog at this age, so short games of one or two retrieves should be adequate.
Your Labradoodle should be able to play hard for longer periods of time, but you still need to be mindful of ensuring joints are protected and that your dog is not getting over stimulated. Rest time is just as important, especially for those days when the weather is not that great or if your the one under the weather!