I want to get a camera that I can use mostly for nature pics and graffiti pics out the window of a moving train, and maybe a butt or two (consensually ofc). Yes I know I’m weird. That said I guess I’ll need a “fast” one for the train, if that is the correct terminology (I think for shutter speed, yes?) The only other requirement is I will not download programs or apps beyond FOSS, preferably something I can just take the SD card out of and plug it into my laptop (linux anyway, most programs don’t like me).
I don’t see myself making this my living (and if I do then I can always upgrade) just as a hobby and maybe some side hustle if the opportunity knocks, so I don’t need the best camera, but I would rather buy nice not twice (unless I leave “hobbyist” and move to “professional”). That said I was thinking maybe a DSLR would be enough for me (if not, I could be persuaded to mirrorless, just trying to keep costs down)? I’ve heard good things about the Canon Rebel, idk. I’m not really trying to go over $1k (and even cheaper than that would be even better) especially if I have to then buy a lens or two.
Any recommendations are greatly appreciated, I have no idea what I’m doing lol.

Thanks for the heads up on those sites, if the local deal I’m working on falls through I’ll be picking one up from the 2nd or 3rd ones you listed, but then I’ll need to get a lens.
Those sites are where I get most of my lenses, FWIW. I really like that they check them and rank them on condition then give a several month warranty on most grades. UPP and MPB show actual lens you’re getting on each listing as well. KEH doesn’t but their descriptions and grades are usually accurate. UPP is my favorite for price and quality but have a much more limited rotating stock of gear. I’ve bought multiple things from all three though.