You are responsible for researching and obtaining all required entry documents, including passports and visas for your host country. Your passport must be valid for more than six months past the end date of your program.
You can find information on entry and visa requirements on the host country embassy or consulate website.
Most likely you will need to obtain a student visa for a semester or academic year abroad. Planning ahead is essential as it may take a long time to process a student visa. If you have to apply at the consulate in person, you may need an appointment which can book up months in advance.
Make sure your U.S. visa is valid for re-entry and have your I-20 signed with a travel signature. If you have any questions on your U.S. visa status, contact your International Student advisor.