Hello Shivam shandilya ,thanks for asking this question on this platform.when you fill form of JEE till your payment process you can make any desired changes but once when you submit your payment then your details are submitted in the form of data sheet in the respected department.but you are not the only one because sometimes by mistake we fill something wrong and want to change that .and for this they give a chance to correct that thing for this you have to be continuously contact with the official website of JEE.thanks 

Hi Shivam,

Choice of application form of JEE for choosing online or pen paper cannot be changed after applying . You have to give the exam in the required mode which have selected  however...

You can edit the JEE Main application details, photograph, signature till the time of payment. Once payment is made and submitted, you cannot make any changes in your application form. However, CBSE gives one correction window but the date of the same is not yet released. If it will happen this year, it will in somewhere in January. I would suggest you to keep checking the JEE Main official website to keep a track on all important dates.

All the best

Shubham Goel