After you add changes to a topic branch or fork, you can open a pull request to ask your collaborators or the repository administrator to review your changes before merging them into the project.
Creating and deleting branches within your repository
You can add or remove branches directly on GitHub Enterprise.
About comparing branches in pull requests
Pull requests display diffs to compare the changes you made in your topic branch against the base branch that you want to merge your changes into.
Creating a pull request
Create a pull request to propose and collaborate on changes to a repository. These changes are proposed in a branch, which ensures that the master
branch only contains finished and approved work.
Creating a pull request from a fork
If you've forked a repository and made changes to the fork, you can ask that the upstream repository accept your changes by creating a pull request.