@Casa823 You can't rent out separate rooms from one listing. As Emiel said, each room requires its own listing. Then you just title each one XX(name of hotel) Boutique Hotel Room #1, XX Boutique Hotel Room #2, and so on. Or give each room a name rather than numbers.
If every room looks exactly the same, you can just duplicate the photos. If there is variation in the rooms, which I imagine there is (different window and door placements, for example) then you need a photo of each room which corresponds to the listing, plus photos of common areas guests share.