Hello Mohan,

I think you know that JEE advanced 2020 will be conducted on september 27 which is just around 45 days from now on.Well, getting a rank under 2,500 in advanced is not that much easy .No problem if you prepared for advanced in your intermediate without considering this lockdown period.you just have to revise the concepts if you have already prepared.

But if it is not the case,like,if you have not started your preparation yet,it is better for you to attend for JEE advanced 2021.Because,you can not take burden on you because you can not just complete the whole preparation within just 45 days.

You are mentioning that,you want to take coaching.We are still unsure that when will coaching centers will reopen.So,you better be prepared for JEE advanced 2021.Once coaching centers reopened,start your preparation seriously by  first understanding the concept deeply and practicing a number of problems and doing mock tests and practicing previous years papers.

Here i am mentioning few books as of my experience

Cengage ->It will be useful for all three subjects for solving number of problems.

Hc verma for physics

Op tandon for chemistry.It will be good for concept.

Himanshu Pandey for Organic chemistry

Hope this helps:)