Hello Himanshu

As, your marks in JEE Mains 2020, is coming out to be 41-43 out of 300. So, with these marks, your percentile and rank are very low. You will get a percentile between and 73.09 - 73.29 which is considered as low percentile to become eligible to write JEE Advanced.

If you are having any quota (SC or ST), then you are eligible to write JEE Advanced. Also, if you are having any physical impairment, then you can write JEE Advanced. You can only write JEE Advanced if you are having a quota, because your CRL is very high and you can't reach the cutoff percentile. So, wait for the cutoff which will be announced with JEE Main result. It will be released after JEE Main exam. After result, you will know whether you are eligible or not.