No.
Only 10th standard students are eligible for NTSE as you are in 11th so you can apply for KVPY if you have PCM/PCB.
For reference, you can go through the below link -
https://school.careers360.com/articles/ntse-2017-eligibility-criteria
https://school.careers360.com/articles/kvpy-eligibility-criteria
Good Luck!!!
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