You might find the location of a file owned by someone else only if that location is shared with you i.e. a folder or Shared Drive.
There are several ways to find the location. If you have opened the file, click on File > Document Details.
If the location was not shared with you, - will be displayed, otherwise a link with the name of the folder will be shown.
It was said that you have "read-only access" but on the Google Drive / Google Sheets jargon the file was shared with you as viewer. You can find the file in "Shared with me" and you could add a file shortcut to your drive or to a Shared Drive. You could only move a file from folder or Shared Drive only if that location is shared with you as editor / manager / content manager.
Contrary as occurs on other file systems, Google Drive doesn't use file paths to "physically " store files, actually a file could be an orphan (no parent folder / root folder but still count against the file owner quota.
To learn the file the whole path of a file in Google Drive, first you have to find the folder / root folder where the file is "located", then recursively get the parent folder until to get the whole path but
- you should have access to all the folders (you will not be able to get the root folder of another user)
- for orphanated files that is imposible, first the file should be moved into a folder.