The librem might work but what can I install on it besides their OS? It also has very limited ram/etc. I've been looking for a single board computer with usb-c

The librem might work but what can I install on it besides their OS? It also has very limited ram/etc. I've been looking for a single board computer with usb-c that's still a reasonable good desktop and haven't found anything. The only contender right now is the motherboard from a steam deck but im not sure that can be taken out and work on it's own.