Will my fiancee visa automatically change to a Green Card (permanent resident card)?
No. After the marriage takes place, your U.S. citizen husband or wife must contact U.S. Citizenship and Immigration Services (USCIS) to change your status to legal permanent resident. This information is given to you when you enter the U.S. For more information, see K-1 Visa: Fiancee Visa to Marry U.S. Citizen.