Adjustment of status is a procedure that allows someone who is in the United States and otherwise eligible to immigrate to acquire lawful permanent resident status through an application to the US Citizenship and Immigration Services Bureau. Not everyone is eligible to apply for adjustment of status (AOS).
Prove that they were admitted lawfully to the United States as nonimmigrants, or were paroled. Unless this requirement is met, with a single exception, it is impossible to file a proper application for adjustment of status. The single exception is for those applicants who qualify to apply under section 245(i).