I lived in Japan for over a year, and don't speak Japanese. I also lived in the Czech Republic and Azerbaijan without speaking Czech, Azeri, or Russian. Obviously, you pick up some words and phrases just by living in a place, and it's possible to find classes or language exchanges if you really want to learn the language. Definitely something to think about if you just want the experience of living outside the US. The UK is not a great place to be an immigrant right now, TBH, and visa prospects are grim.
If you're under 30 you might look into a working holiday visa to Australia or (I think) New Zealand. Those visas are only for a year, but again, experience, and maybe once you've been abroad for a while you'll run into some other opportunities.