Dear, Sir/madam I am qualified 12th pcm with 51.3% can I fill form Jee-main
Assuming your query is related to next year because this year jee main exam is already done so to get seat in NITs, IIITs, IITs & GFTIs student needs to get 75% aggregate in PCM or he/she should be there in top 20 percentile so with this percentage you wont be eligible to get into these colleges but you can try for state Govt and private colleges which accept jee main score/rank to offer admission.
Good Luck!!!