I think you might still need a very basic start on NixOS. The graphical installer makes it pretty easy to install NixOS, but you end up with a system you don’t understand.
This video series is pretty good, especially the first video will help you understand a few things (though the installation part of the video talks about things you don’t need anymore): [video] NixOS: How it works and how to install it!
This video ignores the installation bit because it assumes graphical installation, so you might get less bored: Distrotube — NixOS Is The Power User Distro (Now With An Easy Installer!)
It’s a shame there’s no basic video on using NixOS as a normal Joe. Everybody just installs it and then adds a package or two, without even explaining how https://search.nixos.org works.
Personally, I just read the NixOS manual when I started, everything post-installation is very relevant to you: NixOS Manual
But I also started out pretty comfortable with non-graphical desktop use, so I’m not sure this is as easy to grok for someone who prefers a graphical installer.
NixOS is very different from other distros, to install things you don’t really enter commands into the terminal. It’s more involved, focusing on “declarative” configuration, i.e. you edit some files and then ask NixOS to make the changes you made to the files real. But the above resources should help understand that better.
SnowflakeOS is a project that might be more up your alley, it’s essentially NixOS with a preinstalled configuration for users who prefer a GUI, focused more on helping you get started: https://snowflakeos.org/
It’s not really ready yet, unfortunately, but if you get stuck with NixOS maybe give it a shot, or at least watch that space 