Please guide me, how to resolve this issue.
You do realize that fedora 33 has been EOL for about a year now?
With that said, it seems something has changed a device UUID on your system or a device is failing.
It may be necessary to boot to a live image and use chroot to recover. We need a lot more detail to assist.
If you can get into the emergency shell with the root password then let us know otherwise we will definitely need to assist with a live image boot and the chroot environment.
Thank you for your assistance and response. I returned it using the snapshot.