Hii Mayuri,
You can give the SCB test of IISER Pune after 12th board exam.You cannot give this exam in 12th class.You should study hard and practice regularly for the exam as this Colleges has very less seats to be acquired and there is intense competition.So,All the best.
If your 12th completed in 2019 than you can give SCB of IISER exam. This is the official site detail about SCB exam you can read carefully https://www.iiseradmission.in/eligibility/ .
This link gives you total complete information about your queries and also provide cutoff marks detail.
All the best dear MAYURI
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