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.
You’re incorrect about Brazil. Spanish and English are actually behind languages like German, Italian and Japanese. There’s also a mix of indigenous languages that summed up reach approximately the same number of speakers as Spanish.
Back in the 90s you could still find some smaller towns in Brazil where the majority of people didn’t use Portuguese at all on their day to day. Nowadays you can still find people who only have Portuguese as their second language but pretty much everyone under 80 certainly speaks it.
Understandable, I just looked it up, but it does seem like German and Italian are pretty common, especially as far as immigrant languages go.