If you need to copy the layout to the second floor, you can easily do so by following these steps:
To select multiple items, hold down the Shift key and click and drag your left mouse button over the items you want to select. This will highlight all the desired items.
Once you have selected the items, you can copy them by pressing Ctrl+C (for Windows) or Command+C (for MacOS).
Go to the second floor and position the cursor where you want to paste the copied items.
Use the Ctrl+V (for Windows) or Command+V (for MacOS) keyboard shortcut to paste the copied items to the desired location.
If you need to select numerous items one at a time, you can hold down the Ctrl key and click on each item you want to select.
Note: by following the steps above you will copy the furniture items only. To copy the rooms please repeat each step picking one room at a time.