Hii ,
To get admission in IISER,there are 3 channels
They are
JEE
KVPY
SCB
As you are going through SCB channel ,you have to write the aptitude test which is an entrance exam consists of physics,chemistry and Mathematics subjects.To write that exam the IISER authorities will make the 12 th marks with certain percentage as a cut off.you don't need to get a high percentage but a decent percentage is fine.The officials did not announce the 2019 12 th percentage cut off yet.But a minimum of 60% is sufficient.
Thank you.
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