How do you disable opening Safari on macOS?
You could perhaps configure the Parental Controls to prevent browsing by limiting the websites you can view. (Big Sur may have slightly improved controls than Catalina.)
https://support.apple.com/en-gb/guide/mac-help/mchl8490d51e/11.0/mac/11.0
Though of course, there's nothing to stop you from turning the controls off.
Ultimately, I would suggest that the best solution is a non-technical one.