HELLO AKASH
The eligibility criteria for giving KCET is You need to study at least 7 years in karnataka.
there are various clauses.
The candidate should have studied and passed either 1st and 2nd year Pre-University Examination or 11th and12th standard examination within the State of Karnataka from an Educational Institution run or recognized by the State Government and that either of the parents should have studied in Karnataka for a minimum period of SEVEN years
Well there are various clauses if you fit into anyone of those you can give KCET exam.
But if you want to study in karnataka there is one more exam called as COMEDK which can get you admission into various reputed colleges of karnataka
To check the eligibility clauses visit this link
http://kea.kar.nic.in/cet2019/eligibility_clause_2019.pdf
HOPE IT HELPS!!