Hey there

There is no restriction of stream in UPSC civil services. Any one who passed graduation can give this test. But seeing the recent trend it has been observed that many students get attracted by the royal life of the few students who get selected for in the exam and leave the preparation in the middle or get depressed. 

Find yourself and see if your interest are similar with the exam and if so then start preparing for NCERT books also refer lectures by unacademy.

Check about UPSC 

https://www.google.com/url?sa=t&source=web&rct=j&url=https://competition.careers360.com/articles/upsc-civil-services/amp&ved=2ahUKEwjzjbfQk7ziAhWCfH0KHeMYCawQFjAAegQIAxAB&usg=AOvVaw1MqPo2dBcdPeUDxJp5CAZj&ampcf=1

Good luck