Or is it more if you lived even like 500 meters of a border do you learn the language of the country your in?

That tends to be how it’s done. States tend to be rather protective of their official language, and it’s generally impractical to send your children to school in a different country. Being proficient in the other country’s language is quite common, but to truly be bilingual you pretty much need to be some kind of ethnic or religious minority.