Learn About the macOS Beta Downgrade Options
Before you install the macOS Big Sur beta, you should explore the downgrade options that will bring you back to macOS Catalina.
If you decide that you don't like the macOS Big Sur beta or there are too many problems, you can downgrade back to macOS Catalina on your device pretty easily if you are prepared.
The best way to downgrade is to restore a Time Machine backup from macOS Catalina. This downgrade will take some time, but it will take you right back to where your Mac was before you installed the beta.
You can do a clean install of macOS Catalina if you want to downgrade that way, but you will then need to set everything up from scratch. Figure out your escape plan before you jump into the macOS Big Sur.