AC here are nearly always split units though. Our windows don't slide up, so harder to install that type of AC unit that sits on the sill.
I have windows that slide sideways, and an AC unit with two pipes (intake and exhaust) that go through a piece of plastic sitting in the window's rail.
It's terrible. Super loud, and the room gets hot again in a couple minutes after I turn it off.
Split units are almost always illegal to install because of local urbanism laws, or apartment lot rules.