Hi Ayush Kumar Singh,

According to the latest eligibility criteria of National Talent Search Examination (NTSE), students who are currently enrolled in class 10 from any recognized school/board  are eligible to apply for NTSE exam.

So, after coming in Class 11 you can't enroll for NTSE exam.

Refer here for more info - https://school.careers360.com/exams/ntse

Feel free to ask doubts in the Comment Section.

I hope this information helps you.

Good Luck!