Hello,
For IFS, there is no priority for any particular course. All you need is a degree from recognized University and is Citizen of India/Nepal/Bhutan (there are exceptions). The minimum age should be 21 and maximum upto 30 for General category. And only 7 attempts allowed for General Category.
But you can go for International Relations or Economics in your college level which serves as base for future prospects.
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile