Lets start how to do a PULL REQUEST. For that you need to fork the repository.
Fork this repository Second-PR
Click on Fork Button.
After that open the file which you want to do changes.
College Name is our first file.
Click on the edit button and add your details in the mentioned format.
Last Click on Commit .
After commit you need to do final pull request for that go to pull request section in the repository and click new pull request.
After that Click create pull request and its done.
As simple as that.