Discuss your plans to study abroad with your pre-major and major advisors. Research the options and determine how they fit into your academic plan at Duke. Check out the "LibGuides" at the Duke Library for a wealth of information about various areas of the world and subjects of study. The library has a page of resources for those preparing to go abroad here.
Choose the program that best complements or contributes to your plan. Consider, too, other factors that may be affected by your decision: course sequencing, housing when you return, etc. For instance, if you study abroad during a fall semester it may be that your housing when you return in the spring is not your first choice.