I have got 85 percentile in jee mains.... Am I eligible to take admission in Nfsc?

Hello.
As far as general category is considered so you are on the line of getting admission in NFSC but still it may be little bit difficult to have admission because due to 10% reservation of EWS category there are only 40% seat available for open categories.
And percentile does not cognate with the proper rank, rank vary with different percentile so chances may also vary.
Best of luck.