I think that you have to ask if someone speak English. Many peoples from my country speak other language.

It varies a bit. In the past many Brazilians I had spoken to spoke no English or very very bad English. Since joining italki I've talked to some who spoke some English, one who had nearly natural grammar in English (In writing anyway, don't know about talking). I would imagine it's taught regularly, but as anywhere it will vary with the persistence of the student and quality of the teachers.