Nixpkgs can be used without knowing anything about nix. You can install almost anything by just running e.g.:
nix-shell -p cowsay
The requirement for that is the nix package manager but that should be easy to install. But yeah getting into Nixos with flakes and all that stuff can be hard.
Pretty much, yes. Although most of the guides install nix via curl. You can find the recommended installation procedure on the official nix website.
What I'm right now also realizing is that i switched things up.
nix-shell -p curl
creates a shell with the curl command temporarily available. If you exit this shell it's gone. I use this all the time if if i don't want to pollute my system with programs I only use once. If you want to permanently install something you have to usenix-env -iA nixpkgs.curl
. But don't take my words for granted, since I have never tested this on a non-nixos machine.Note: You can also see how to install something by clicking on the package title in the nixpkgs repo.