Click "Customize-Customize Ceiling" and select the top surface to enter the ceiling interface. Select the ceiling template in the left "Ceiling-Parametric Ceiling", click on the selected ceiling template and drag it into the room. This way the ceiling is applied to the room automatically.
You can adjust the parameter of this ceiling in the right property panel. When you select another template and drag it into the room, it will make a replacement for the ceiling.
