does this help
https://support.norton.com/sp/us/us/home/current/solutions/v59650017
https://community.norton.com/t/restore-files-from-a-backup-on-a-external-drive/244717
https://community.norton.com/t/back-up-computer-to-external-hard-drive/245193/17
https://community.norton.com/t/extract-many-years-old-backup-from-external-drive/355071
https://community.norton.com/t/norton360-lokale-backup-satze/248283/8