Just a caution about wording.
Adjoining rooms just are rooms that are next to each other. They may be right next to each other or they may be the next room number, but are across the hall from each other or separted by something like a Housekeeping closet, the ice machine room, etc.
Connecting rooms are adjoining rooms that also have a door inside the room that can be opened so you can go from room to room without going into the hallway.
I've seen a lot of posts where people were disappointed that they requested "adjoining rooms" and got rooms that were next to each other instead of ones with a door between. They got exactly what they requested, but not what they expected.