hi,

see first of all you have to take admission in 12th course, as per your choice of stream. for upsc exam candidates stream or study of back ground does not matter. once you complete your 12th, you have to take admission in bachelors degree in a recognized university or university affiliated colleges. so you may take any of the course like b.a/ b.sc/ b.com/ (//b.com/) mbbs/ b,tech/ bds etc

while you are in final year of graduation you may start preparing for upsc civil service, usually it takes intensive learning of 1-2 years, depends on candidates ability to grasp the syllabus. you mus attempt mock exams as well as revision lessons to get a good score.

to know in upsc exams details follow our article at below link:

https://competition.careers360.com/exams/upsc-civil-services-exam