hi,

upsc civil service exams can be attempted from any branch of studies. the eligibility criteria for upsc civil services is  candidates must have completed bachelors degree course in any discipline from a recognized education board. however it depends on you in which of the course you find interest. if you have decent score in mathematics, physics, chemistry you may opt for bsc or engineering courses. however if you are not inclined to do bachelors on science stream you may go for b.com (//b.com) or b.a course.

b.com (//b.com) would be easier compare to engineering courses.