My boyfriend and I are getting married in a jail he is being held on a inaggation hold how do we get married and what all happens

I don't get it, he is being held for deportation? A marriage won't change this, he is being deported cause he entered illegally. Once your married you can sponsor him to move to the US but the deportation then marriage will make them look very closely at this application as it seems like a marriage of convenience.

You can get married and once he is back in Mexico file for him to come to the US as a sponsored spouse. Then just see what happens