It’s been about 2 weeks since my last comment. I am back to finish my thought!
Not sure if an apology is warranted although I appreciate your sincerity.
This is what I was referring to:
From the official README.md for home-manager:
Unfortunately, it is quite possible to get difficult to understand errors when working with Home Manager. You should therefore be comfortable using the Nix language and the various tools in the Nix ecosystem.
If you are not very familiar with Nix but still want to use Home Manager then you are strongly encouraged to start with a small and very simple configuration and gradually make it more elaborate as you learn.
Easy does it. I am determined to start small. I’ll get there.
NixOS has been around since 2003 but flakes is only about 5 years old (if I understand correctly). So NixOS should be able to stand up on its own feet with nixpkgs alone and then add flakes as I go along.