The long rumored Dream Suite feature is finally coming to Animal Crossing: New Horizons. For this you will need to have Nintendo Switch Online.
In this Animal Crossing: New Horizons there will be no building to find Luna, we will only have to sleep in the bed of our house. Once we fall asleep, we can visit islands of friends with their visit code to go to their islands.
The first time you speak to Luna, she will ask you to create a dream code for your island. This code will be the one that you must communicate to your friends so that they can go visit your island with Dream Suite in Animal Crossing: New Horizons.
Note that upgrading from your starter tent into a full house will be required first to unlock the dreaming feature, as well as an active membership to Nintendo Switch Online as it is considered an online function.
Dream suite in Animal Crossing: New Horizons
Really what is being visited in the Dream Suite in Animal Crossing: New Horizons is a copy of the islands of our friends. As for what you can do when exploring player islands while sleeping, you can explore the contents of your heart, but nothing is permanent as nothing you do will be saved.