U.S. citizens can vote in U.S. elections while studying abroad.
The U.S. embassy and website for your host country will provide voting abroad resources. In some countries, you can fill out your ballot online.
Determine if you are registered to vote, and in which state. Your state of residence can be either your home state or your college state, but you can only register to vote in one state. Look up deadlines for ballots and for requesting absentee ballots.
The Overseas Vote Foundation has helpful information specific to overseas voters!