Dear Pratik,

For your kind information, you can easily upload your marks for Delhi University by following these steps:

https://ug.du.ac.in/index.php/site/index

Log in, with your registered email id and password, then on left-top corner click on academic details then you have to upload your scanned mark sheet, then changing your result status to pass you can enter your marks.

I hope that'll help you, best of luck for your further career updates.