sir ,i have applied gate 2021 for only 1 paper but now i also want to choose 2nd paper can i made this change in edit application...

Hello,
The last date to apply for GATE exam 2021 is September 30, 2020. After the application period is over, the authorities will open the correction window for the GATE 2021 application form.
You can change your previously selected exam centres and the paper you have chosen. You can then include the second paper you wish to appear for.
You need to pay a fees for the correction. Please keep an eye on the official website of GATE exam 2021 for the dates for application form correction window.

Please visit this link for detailed information about GATE 2021 application form correction window

Hope it helps