Hi Suyash.

The statr board in Maharashtra has not announced it's cut off for IIT according to the top 20 percentile for 2018 yet.

But in 2017 the cut off announced by Maharashtra board was 386 marks out of 650. Considering your marks and the previous year cut off you seem to have a fair chance of falling under the top 20 percentile and being eligible for IIT. Hope for the best!