Charlie wants to know if he can make a bootable backup of his hard drive with macOS Big Sur using Carbon Copy Cloner. Leo says he can, but it's not all that easy. Apple has changed the way it does things ... again. It's more secure, sure. But only Apple can sign it. And that means he can't do it anymore without making a clone of the hard drive, installing macOS Big Sur to it, and let Apple sign it. BTW that's how ChromeOS works.