How to Roll Back from macOS 12 Monterey beta to macOS Big Sur

To begin with, it is worth noting a couple of nuances. If you backed up your system before installing the beta, you could restore your data from a copy of Time Machine.

To roll back, you need to format the disk on which the beta version is installed. If you installed macOS 12 beta on a disk partition, you could simply delete it, and your Mac will boot macOS Big Sur.

Here is a complete guide-

How to Roll Back from macOS 12 Monterey beta to macOS Big Sur – TechRechard