Hello aspirant this year the qualifying cutoff of jee mains 2019 for obc category is 74.31 .so according to this you have not cleared the cutoff therefore you are not eligible for jee advance paper.

And you have score 75 percentage minimum in your 12 exam to appear for jee advance

For more information visit this link

https://www.google.com/amp/s/engineering.careers360.com/articles/jee-advanced-eligibility-criteria/amp