Set Expiration Dates & Temporarily Share Google Drive FoldersYou create a folder in Google Drive and share it with Public or a small group. You then specify a date/time when you want that shared link to expire. The script, at the specified time, will create a copy of your shared folder and delete the original one. Thus the shared links would no longer work though the folder and files will stay in your Google Drive.
When you put a file in Google Drive into a Folder it is labeled with that folder name and removed from the view of My Drive. When you put a file in multiple folders, the file is not in multiple folders it really just has multiple labels.