Honestly, good for you. I switched about a year and a half ago after using Windows literally all my life (well, from when I was 5 years old in primary school anyway).
Never looking back. I now know what a good PC experience is like. One that doesn’t bombard you with ads for its own browser and requests to track you every time it stops in the middle of what you were doing to force an update that only makes your experience worse.
I personally use Nobara on my main PC and OpenSuse on my laptop, but whatever you go with, I wish you a good time. (And know that if you don’t, there’s always a distro out there that will fit your usage better!)
Samsung TVs run Tizen which is their own OS, rather than a skinned Android TV. It’s pretty minimal so you need some other box or stick if you want a good watching experience, but it doesn’t do anything hostile as long as you turn the tracking bs off at setup, and there are no ads in the UI (at least on the 2019 model my parents have).
There’s no truly open source TV OS though :( I miss Firefox OS