Answer
To enter the USA you will need a valid passport, visa and Form I-20. A visa does not guarantee entry into the United States. A visa only allows a foreign citizen to travel to a U.S. port-of-entry (generally an airport) and request permission to enter the United States. The Department of Homeland Security (DHS), U.S. Customs and Border Protection (CBP) officials at the port-of-entry have authority to permit or deny admission to the United States.