Make sure to make regular backups of this folder:
/Users/<username>/Library/Containers/com.blackmagic-design.DaVinciResolveAppStore/Data/Library/Application Support/Resolve Disk Database/Resolve Projects/Users/guest/Projects/
If you want to open it in Finder and you’re not sure where to start, follow this advice to find your way to /Users/<username/Library/. From there you’ll be able to navigate to Containers/ and further.