Hello,
You can show your NIOS result during the document verification for admission. However, since you mentioned CBSE in your JEE Main form, there might be an issue.
It's best to contact NTA (JEE Main authorities) (https://www.nta.ac.in/contactus) to check if any correction is needed. Also, confirm with the college admission office whether they accept NIOS results. Some institutes allow it, but policies may vary.
For official confirmation, visit jeemain.nta.ac.in or contact the respective college.
Hope it helps !
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