How can I divorce a immigrant if I dont know where he is and I have 4 children and his name are on all of the birth certificates?

A divorce is a lawsuit and begins when the person seeking a divorce files a Complaint for Divorce.  ONce your file the lawsuit, then you must serve your husband with the lawsuit.  If you do not know where your husband is, then you can seek permission from the court for an alternative method to serve him with the lawsuit such as publishing notice in the newspaper.  If he fails to respond, then the Court may enter the divorce and determine the issues of custody, parenting time, child support, alimony, and property division even in his absence.  Children born during a marriage are deemed to be the children of the married couple.  If your husband appears for the divorce, he can argue that a child is not his base upon his absence.  If you want the true father to be the legal father, you can address that issue with the court.  Stu Shafer