“How long will my puppy have to keep using the puppy playpen for?”
That all depends. Your puppy playpen has played a vital role in keeping your pup safe, but understandably you don’t want to have it up in your home forever.
When you are relaxing, and able to supervise fully, let your puppy have the freedom to explore. As he hasn’t been left to his own devices to pick up bad habits like chewing wires, he may show no interest in them. If he does start to mouth them, call him to you, and give him something more appropriate like his own chew toy. Eventually, he will learn what he can chew on and what he can’t.
As he is only ever out of the playpen when fully supervised, this speeds up the training process. He or she will more quickly learn what is acceptable behaviour and what isn’t.
Just like a crate, never use being put in the playpen as a punishment. It must always be a happy place for your pup.
Once you can trust him with you in the room, you can try putting up a stair or dog gate on the doorway and give him the freedom of one room. That way he will be able to still watch the comings and goings of his human family without getting up to too much mischief.