USA: Spanish. I’m learning Spanish, and I think as a whole it’s like 18% of people in the USA but I feel like you’re likely to encounter some Spanish speakers and make friends even if not everyone speaks Spanish here.
Brazil: It looks like Spanish is also the second most spoken language with 4% or English with around 5%. I’m sure you’re more likely to find people on the Internet who speak it.
French: English, apparently a quarter of the population speak it??? Not sure how likely you are to find someone in the wild speaking it, but on the Internet, a lot of people.
Here in South Limburg it’s a mix of Limburgish/Dutch>German>English and French. Within a 20 minutes drive from my house, I can be in Germany, Flemish or French speaking Belgium, mostly anyone will understand German, Dutch or English near the border, French is a little harder, at least for me.
I am from Amsterdam, my friends all speak Limburgish dialect with eachother and I understand it, but I don’t speak dialect, and they will adapt to normal Dutch.