If you want to get chance in IIT, you have to qualify JEE Advanced with a good rank. If you have already cleared JEE Main, you have chances to get into NIT, IIIT or GFTIs with JEE Main 2020 rank. You may get into various private institutes too with your JEE Main rank.

NITs, IIITs, GFTIs and many IITs have fee waiver scheme in which students get complete or partly waive of fees as per their family income.

Hope you understand. Good luck.