Can I adop my nices that live in mexico. I'm a single mom of two

Provided you're a "fit" parent, I don't see why not. Just because they're your nieces doesn't mean you're not allowed to adopt them. Many people adopt out of country with no problems. As far as the single already mother of two, I don't know how much courts would like that, but get more info on the whole process, as single parent adoptions aren't something I know much about. Good luck.

As long as their mother and father are willing to sign over their rights, and you apply and get the proper visas for them