For AADHAR CARD correction you need to visit your nearest Aadhar Seva Kendra so that you can do the necessary correction. Now you can apply for the JEE MAINS & by the time of counselling and document verification make it sure that the Aadhar card is corrected or else problems may occur during the admission.

For the Aadhar Seva Kendra consider the link provided below:

https://uidai.gov.in/ecosystem/enrolment-ecosystem/aadhaar-seva-kendra.html

I hope this helps. Wish you a great day!