Hi

If you want to give NEET exam then you are required to do class 12th from PCB (physics,chemistry and biology).

Since you were an PCM student, you can study class 12th again from NIOS (National institute for open schooling).

After that, if you get qualifying marks in class 12th PCB which is 50 percent for general category and 40 percent for OBC/SC/ST category, then only you are eligible for NEET

For more details, please refer to this article

https://medicine.careers360.com/articles/neet-eligibility-criteria

Best of luck