Hello Aspirant!

According to KVPY eligibility criteria 2019 of SX Stream :-

'Students who are enrolled in XII Standard (Science subjects) during the academic year 2019–20 and will join any UG program in Basic Sciences i.e. Physics/Chemistry/Mathematics & Biology leading to  B.Sc./B.S./B. Stat./B. Math./Int. M.Sc./Int. M.S. for the session 2020–21, provided they have obtained at least 75% (65% for SC/ST/PWD) marks in aggregate in MATHEMATICS and SCIENCE subjects (Physics/Chemistry/ Biology) in their X Standard Board Examination during the academic year 2017-18 are eligible to appear for the Aptitude test."

Source : http://kvpy.iisc.ernet.in/main/eligibility.htm

So, it seems like you won't be eligible to sit for the Aptitude Test for SX stream this year.

But if you are presently in the first year of your graduation, then you can apply under SB stream.

- For taking up the fellowship, you must have to obtain 60% (50% for SC/ST/PWD category) aggregate marks in the 1st year final examination of B. Sc. /BS/B. Stat. /B. Math./Int. M. Sc. /MS, if awarded.

-Also, you must have secured minimum 60% marks if you belong to General category (50% marks for SC/ST/PWD category) in aggregate in Science subjects in your Senior Secondary Board Examination (10+2 level) to get the fellowship.

Feel free to comment below your doubts (if any).

Hope this answer will help you.