Raspberry Pi
A [Raspberry Pi] is a amazingly cheap but working computer at the size of a deck of cards.
After installing it works fine as as headless server but if you want to use it as your desktop system there as some thinks to take care of.
You may need a lot more storage locally (e.g. to sync with your cloud-storage). You can plug in any USB device and use that but you can put the installation imaged on the USB device and boot from that.
X11 applications
RaspiOS is using wayland as backend for the displan server backend. Although it is said wayland is the future and does have xwayland that should allow X11 applications to run some don't. Applications will just show you 'cannot open display' or something similar
With this help [1] I found the solution.
- echo $XDG_SESSION_TYPE
- If this shows 'wayland' that is your backend
In raspi-config 'Advanced Options' - 'A6 Wayland' select X11 and reboot your system.