hi,

eligibility criteria for neet ug exam is candidates must have completed or appearing in 12th exam with physics, chemistry, biology as a mandatory subjects. marks criteria for general category candidates is , candidates have to secure 50% aggregate score in physics, chemistry and biology. for sc/ st/ obc candidates marks criteria is 40% aggregate in pcb.

however since you have failed to get the pass score in physics and chemistry you have to retake the exam. now it depends on in which board you have appeared in 12th exam. in cbse board students are allowed to appear in compartment exam in the failed subjects ,  however if the candidates are failed to clear the supplementary exam, candidates have to  again repeat the 12th course.