A newborn baby can be taken out of the house at any time in it's life.
There's no need to wait and keep the newborn baby in the house as it's safe to take them out of the house whenever you want too.
I've taken my newborn baby out of the house as soon as I got him home although I had a doctor tell me that I should stay in the house with him for at least a few weeks.
But that is not needed as there's no harm in taking a newborn baby outside.
You have to take the newborn baby outside of the hospital to bring them home so it's no different taking the newborn baby out of the house.
I could not stay cooped up in the house with my babies anyway and I needed to go out and get food, supplies or just go out for a walk.
I would put my newborn baby in his stroller and go for a walk as long as it was not too hot or too cold outside.
If it's too hot or too cold then stay in the house but if the weather is just slightly cold bundle the newborn up and go ahead and go outside even for a few minutes.
The fresh outside air and sunshine will improve the babies health and not harm it.