Golden Retriever puppies want to keep their living area clean and generally will not soil that space, especially if it's their sleeping area. Crate training or small space confinement helps in this regard. If not, consider attaching a leash to him to confine him to his sleeping area. As stated, he will not want to go potty in or near his sleeping area so upon awakening (even during the night) expect him to let you know he needs to go potty. This is an important time in his potty training process. He'll learn upon awakening, I go outside first.
If you have to leave your puppy home alone during the day, confining him to his sleeping area may be a good idea. However, you may need to schedule a consistent time midday for you or someone else to go home and allow him to relate himself. Young puppies can not hold it for 8 hours. In a perfect world, taking some time off from work for the first few days would be ideal.