For NEET 2025 registration, your state of eligibility for the 85% state quota seats will be Chhattisgarh since you have completed your entire schooling there. However, your OBC certificate is from Andhra Pradesh, which may not be valid for OBC reservations in Chhattisgarh. Each state has its own OBC list, and the certificate must be issued by the respective state authorities.

To claim OBC benefits in Chhattisgarh, you need to obtain an OBC certificate from Chhattisgarh authorities. If your caste is listed under OBC in Chhattisgarh, apply for a fresh certificate. If not, you will be considered a General category candidate for state quota seats in Chhattisgarh but can still claim OBC benefits under the All India Quota if your caste is in the Central OBC list.