To add a rooms you first need to have at least one room type configured. To do so go to Backoffice -> Room Types and click Add +
After the form is opened you can fill all the desired information about room type, facilities, price and taxes.
Rooms
Now you can add a room as a unit. The steps are similiar to adding a room type. Just navigate to Backoffice -> Rooms and click the + button to add a new one or click on a room name to edit a room.