It depends.
You can basically always use the crappy ones made for general touchscreens to replicate your finger. You can’t use a real one with features like Apple Pencil/surface pen/wacom without an extra layer built into the screen to recognize them.
FWIW, my daily driver is a Lenovo Yoga with Ubuntu and the active pen works just fine with that. That support is definitely there.
it wouldn’t be hard at all you just buy a stylus that works like a finger
With the catch that it works like a finger meaning fat and imprecise. A stylus like the surface has is more like a pen and needs hardware in the tablet to function.
Did you ever use the Nvidia Shield Tablet stylus? It was a very thin and precise passive stylus that worked on any touch screen. It was pretty nice. They probably only sold a handful of them, so there was no gen 2. I happen to know someone who was working on that project, so they let me play with it.
