NEET is the entrance examination for admission to MBBS,BDS, Ayush and Veterinary courses across India. This includes AFMC, AIIMS, etc. So 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. Coming to your case, you have secured 54% in Physics, Chemistry and Biology. Now if you have passed in your Theory, even if you scored lesser in Theory than in Practicals, it is still ok. You are eligible for NEET. And take admission to  Medical Colleges across India including AIMS, AFMC, etc. But AFMC has  TOELR, PAT and Final round of Interview. With 54% in Physics,Chemistry and Biology, you are eligible for appearing for NEET which is the entrance examination. But for a seat, you have to score more than 650 for AIIMS and 625 for AFMC.