NEET is the entrance examination for admission to MBBS,BDS, Ayush and Veterinary courses across India. And its validity is for 1 year. Now there are 2 things to it. NEET is also a mandatory entrancce exam for studying MBBS, BDS abroad. For those Candidates who want to study Medicine abroad, their NEET score is valid for 3 years. So lets say if you want to study MBBS/BDS abroad and you appear for NEET 2020, you can use it even in 2022 to study abroad. But if you want to study MBBS/BDS/Ayush/Veterinary courses in India, then your NEET 2020 score is valid only for 1 year. The flexibility of 3 years is for students who want to study abroad because the admission process for Foreign Universities is usually quite lenghty process. But in India, to study MBBS/BDS/Ayush/Veterinary courses, you need to fulfil the eligibility for NEET, score good in NEET and appear for Counselling and secure a seat. And for both Domestic and Foreign admissions, to be eligible for NEET, you should have completed your 12th, passed in all subjects and secure a minimum aggregate of 50% in Physics, Chemistry and Biology. It is 50% for General Category, 45% for PWD and 40% for OBC,SC,ST. Now if you belong to OBC Category, the Category you belong to should be also listed in the Central OBC list. Or else you will be considered as General Category and so you have to secure a minimum aggregate of 50% in Physics, Chemistry and Biology. This 50% is inclusive of the Theory and Practical marks scored in Physics, Chemistry and Biology collectively. You needn't score 50% in Physics, 50% in Chemistry and 50% in Biology separately. You need an aggregate of 50% or 40% depending on your Category as an aggregate in Physics, Chemistry and Biology. And along with Physics, Chemistry and Biology, you should also have studied English as one of the core subjects in your 12th. Just to answer your question, you cannot take admission in BHMS 2 years after you appear for NEET. Your NEET score is only for the Academic year you appear for NEET.