Do i need to do something other than taking the SAT to apply and get accepted from Duke?

Duke is one of the top-tier colleges called the "Ivy League".
Ivy League colleges typically look at applications with X-Factor (something extra beyond excellent academic credentials).
A good GPA score in your high school transcript and SAT scores 2250-2300+ (ACT score: 34-36)** is a must for applicant.
Along with that, focus on something you are good at and establish your credentials as your region, country, nation's best.
End of the day, the Ivy League colleges look to see passion in an applicant in the major they are applying - e.g. doing internship in an university lab/company shows you are thinking to build a career in that field.

** Source: Applicants I know who got accepted to Ivy League or top-tier private schools

Hello, SIna! I see that you have had two responses so far to your question about Duke University, and the advice they provide is right on target. I was fortunate for part of my career to work at Duke and I got to know hundreds of its students and alumni. There was a common trait that most of them possessed and that was an enthusiasm for learning and an optimism about the future. Judging from your brief statement about wanting to return to your country after earning your degree, I think you have a great story to tell. Schools like Duke are always interested in admitting students who will add character and diversity to each class, so if you can tell your story effectively in your essay, supported by letters of recommendation, you will have a good chance of getting admitted. It is true that good GPA and SAT scores will help, but they really only tell Duke one part of your story . . . that you can handle the level of academics needed to compete and contribute to your class. What really makes the difference in the admissions decision is how you explain the importance of Duke in your own future. I think you can have a compelling story because of your background and goals. I hope I'm not too late in helping you achieve your goal.

The best recommendation is to contact Duke's Admission office . You can sit down with them and discuss everything you need to do to get into their school. Also, meet with the financial aid office while you are there.

Hi, Very well said. Duke is a great school and a good choice. Like all schools Duke will require a high GPA. You need to make sure that you do not lose sight and focus on your studies. Other that your GPA, you should also have a powerful essay which reflects your life experiences in a manner that Duke feels that they will benefit by having you there and contributing. The essay will need to be genuine and support all the the things you have done so far. SAT or ACT score are important as well. Please remember that you are competing with top students from all schools.

Good luck!