PCM student can appear for NEET if he is at least 17 years old as of December 31 of the year of the examination and if you have passed class 12th with physics Chemistry English and Biology .you need to at least have Biology as additional subject to because then you are not eligible for me .if you have it as an additional subject and you need to study hard  for NEET. AS bIOLOGY COntributes to half of NEET you need to either have it as an additional subject atleast. even if it is not a core subject then also it is okay but it has to be there as an additional subject NEET ELIGIBILTY