Well, yeah. English is perhaps the most common language in the world.
I live in Wales. welsh was taught in schools but I never learned it. Never had the need for it. I only met 3-5 people in my life where Welsh was their primary language.
That's different for me. While school's primarily using Indonesian language, they taught Javanese and English language too.
I used mostly Javanese language for conversation in my hometown,including to my friends and parents.
It's after I married and move to another town that I started using Indonesian language. Especially since my wife and kids couldn't speak Javanese.