Linux

Thanks for the explanation. So it works similar to the system partition on windows.

Yeah, same bit. Just put everything on another drive/partition and then mount that on /home (so you get /home/user) and that's it.

I somehow struggle a little to understand the role of distribution. When researching how to install Linux, it seemed like an important choice with lots of differences between the various distributions. Some are based on arch, some fedora or ubuntu. It seems like all need different types of packages to install software. And so on. A little ironic, that this is less a problem when running Windows executables through a compatibility layer like wine.

Distributions are essentially just a selection of the basic software required to make a system work. Things like, what version of the kernel you will start with, what init system (systemd is the current popular choice, but sysvinit is still widely used). Then there is the package manager, which is responsible for installing/updating all software on your system (you can install software without the package manager, but here there be dragons) and often a distro will include a Desktop Environment (which is, itself, another package of various software maintained by another group) like KDE Plasma, Cinnamon, XFCE, etc and some default software packages (like, LibreOffice, Firefox, or Steam).

There's a ton of little differences between distros in how they do things. Like one distro may release a full system update periodically and that update will have been in testing for months to ensure stability (Debian). While another strives to ensure the most current version of all software is available (Arch).

Often, groups will like how one system works, let's say Arch, but want to try something else, like adding a graphical installer, and adding some additional software and they'll create a new distro that is built on top of the work done by the Arch distro. This is why you see them described as Arch-based(EndeavourOS) or Fedora-based(Nobara).

That being said, there is no major differences between KDE Plasma that was installed on top of Mint and KDE Plasma installed on Arch. They may have different versions which are available in their respective package repositories, but it's the same software. Mint may not be on the same Kernel version as Nobara but they're all using some version of the same underlying Linux kernel code. Systemd is Systemd on Bazzite, Mint or Debian, etcetc.

I'm glossing over quite a bit and there are exceptions to almost everything I've said but I'm just trying to give you the broad strokes.

Part of the draw of Linux is the ability to swap all of these different components around as you will. Distros are simply popular configurations/design ideas that have a community built around them.