Hello,

Yes, definitely you can continue to pursue your science stream if that interest you. But basically as suggested by experts graduation subjects like sociology, social science etc has more advantages than a science subject.

And basic eligibility for UPSC is to have a graduation degree.

• Any Indian citizen who is a graduate and above the age of 21 can take the exam provided he fulfils all the other eligibility conditions for the UPSC exam. Students from different streams take this exam including science, arts, commerce, engineering, medical, etc.

https://competition.careers360.com/articles/upsc-ias-syllabus/amp

Hope this helps!!