I use PathSync (
https://www.cockos.com/pathsync/) to daily copy my entire Project directory to a second drive. And then, also using Pathsync I regularly copy the entire Project directory to a detachable USB disk, that I then keep in a safe place until the next time that I backup to it.
You cannot have enough backups. Having valuable stuff in three different places is the minimum. The extra valuable stuff, like finished projects, I copy to cloud storage and archive also there.