I agree that the gatekeeping isn’t a good thing, but you should learn at least the basics of the CLI. It will give you a better understanding of what’s going on behind your GUI and makes troubleshooting and fixing problems a lot easier.

Definitely not required but it is absolutely a skill worth having.

Then you don’t understand git or source control in general. If you don’t commit your changes, then you discard any changes, you’re set back to the last commit. Discarding changes also includes any un-committed new files.

No, it means the printer driver is running a web server to host the status page. Localhost is literally your computer.