A great way to learn the basics. It’ll be old, but that’s ok. It’s going to cover all the shell basics and then more. It’s still going to be useful, it’ll cost you pennies, you’ll be able to dip into it when you want, and you’ll be giving to a good cause.
If the internet is gone I have no need for a Linux box.
E: and if it is really just me in my own LAN then I have the man pages