Which Bachelors course should I pursue to become an IAS officer?

If you are sure that you want to be an IAS officer, you should go for BA in public policy & administration course in UPES, Dehradun. As the subjects taught in this course are of political interest and this college is also providing IAS training classes along with this course. You can check more abou

You could go for any Bachelors course as it won't matter. Start taking coachings for civil service exams. (HT's BYJU's classes offer this kind of coaching)