Welcome.
I know that you could get a crate for him to sleep in. He will be safe and won't wonder around.
Good luck with him. Sounds like you rescued this poor little guy and are giving him a good life.
I'm sure there are others who might have more advice.
You will love having a small dog in your life.
It is also my understanding that you cannot take them out unless they have had
all of their puppy shots, as they aren't immune yet.