Hi there, 

NEET is conducted once an year for admissions in courses of MBBS, BDS, Ayurveda, Homeopathy and related medical sciences.

For general category, to be eligible to write NEET one needs to have a score of 50% aggregate in class XII boards with Physics, Chemistry, Biology/Biotechnology as the subjects. 

As you have mentioned that you have 56% marks you are clearly eligible to write NEET and if you crack the examination with a good rank then surely you can study MBBS. 

Your class XII percentage only matters in becoming eligible for writing the NEET examination. Once you crack NEET your class XII boards percentage won't matter at all. 

Hope this helps. 

Check this link for more information: https://www.google.co.in/amp/s/medicine.careers360.com/articles/neet/amp

Wishing you luck!

hii Sourav

you need to worry you have manageble percentage but you must have the score minimum like this  as per category UR - 50%, OBC/SC/ST - 40%, PWD - 45% (minimum aggregate marks only for PCB subjects) p: physics , C: chemistry B : bio

for greater knowledge see the below link

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

regards