I'm a 19 years old female. I was born in Mexico and my stepdad adopted me here in the US in 2009 so my last name was changed to his in my SSN card and green card whereas my Mexican passport still has my previous last name. I was wondering if I am able to leave the country for example I'm thinking on going to Japan this October and I don't know whether I'll be able to go or not because of my last name change or do I have to go to Mexico and get it fixed?
Do you know how long it would take? Even if the adoption was here and in Mexico I still have my mom's last name I can change it?