Can i get my TEFL/TESL certification even if im illegal?

So i talked to my lawyer and he says i have to wait 2 or 3 more years to get my green card, My mother brought me here when i was 4 and i am now 20 years old. But i want to become an esl teacher so i can work in south korea?? Can i get my certification while im waiting for my papers? My lawyer said im not allowed to go back to mexico until i get my papers. And i really want to finish college so i can leave to korea.