How do I add iCloud drive to Favorites in Finder window?

Due to an accident with a mouse with a dying battery, I managed to remove iCloud drive item from the Favorites in the Finder window. If you do it with one, they're all missing it. So how do I restore it? I can't find any way to do it. Help articles are utterly useless as they say nothing on the matter. I don't even know what iCloud drive is and yet I have apparently permanently removed it from the favorites list.