How to rollback from Catalina to previous versions?

Question

macOS

Please tell me, I want to roll back from Catalina to any other version of macOS. However, I have this problem: in recovery mode, disk utility does not allow me to click the "erase disk" button. The button is simply inactive, it is there, but it is impossible to click on it.
15" MacBook Pro 15" Catalina Version 10.15.2 (19C57).
What could it be and how to solve it?

Answer 1

https://support.apple.com/en-us/HT204904