If you fail to manually save your Pages content at least once, then Pages does not autosave your work, and quitting Pages will lose that content and any temporary files. Any documents that you create in a macOS guest account will be removed when you sign out of that account. This is by design.
Otherwise, a properly saved document in a regular user account on macOS or iCloud Drive will not be automatically removed after an arbitrary timeframe. However, Pages will continue to save documents to the same folder location until the user changes that location, and not remembering that folder location could give the impression that the files have been magically deleted.
No Apple employees participate in these public user-supported communities, nor will they read your post. As fellow users, we are not employed by Apple and determine our participation time, not based on user urgency.
If you were using Apple's Time Machine to back up your work to an external drive, you might have already recovered any "lost" files by now.