julia-emacs VS ergoemacs-mode

After that for basic julia support you'll probably want to install julia-mode. There's instructions there in the readme about installing it from melpa. You should be able to just add those lines to your init file after (package-refresh-contents).

It's a tiny tweak that gives something like 1% of the functionality.

The real, useful, working CUA mode for Emacs is here:

https://ergoemacs.github.io/

If you start with framework you might not learn enough to solve problems later, but using it later to simplify your config should be ok. For example ergoemacs http://ergoemacs.github.io/ is a nice way to make Emacs more ergonomic and easier to use(if having problems with default configuration).

For example I use https://github.com/ergoemacs/ergoemacs-mode, with some commands that I have acquired as muscle memory from using Emacs/mg for long. And still I use nano when I need to do small edits to a file. I also do it almost without thinking about it, especially when doing "sudo nano whatever". Mg should be better for me, but nano is engraved into my palms for some reason.

That documentation seems very outdated. The changelog is from 2013 and that function was removed (according to an issue) before 2015.

Xah Lee and friends maintains a mode called ErgoEmacs that implements most of the changes he proposed: https://github.com/ergoemacs/ergoemacs-mode