Update PR documentation (#23620)

This updates the PR docs and explains how to work with PRs, for those
who may not know.

It was mentioned that this page could explain PRs a bit better, in case
some users are not familiar with GitHub or similar forges.

Signed-off-by: jolheiser <[email protected]>

Author: jolheiser

docs/content/doc/usage/pull-request.en-us.md

@@ -15,9 +15,45 @@ menu:
 
 # Pull Request
 
+A Pull Request (PR) is a way to propose changes to a repository.
+It is a request to merge one branch into another, accompanied by a description of the changes that were made.
+Pull Requests are commonly used as a way for contributors to propose changes and for maintainers to review and merge those changes.
+
+## Creating a pull request
+
+To create a PR, you'll need to follow these steps:
+
+1. **Fork the repository** - If you don't have permission to make changes to the repository directly, you'll need to fork the repository to your own account.
+This creates a copy of the repository that you can make changes to.
+
+2. **Create a branch (optional)** - Create a new branch on your forked repository that contains the changes you want to propose.
+Give the branch a descriptive name that indicates what the changes are for.
+
+3. **Make your changes** - Make the changes you want, commit, and push them to your forked repository.
+
+4. **Create the PR** - Go to the original repository and go to the "Pull Requests" tab. Click the "New Pull Request" button and select your new branch as the source branch.
+Enter a descriptive title and description for your Pull Request and click "Create Pull Request".
+
+## Reviewing a pull request
+
+When a PR is created, it triggers a review process. The maintainers of the repository are notified of the PR and can review the changes that were made.
+They can leave comments, request changes, or approve the changes.
+
+If the maintainers request changes, you'll need to make those changes in your branch and push the changes to your forked repository.
+The PR will be updated automatically with the new changes.
+
+If the maintainers approve the changes, they can merge the PR into the repository.
+
+## Closing a pull request
+
+If you decide that you no longer want to merge a PR, you can close it.
+To close a PR, go to the open PR and click the "Close Pull Request" button. This will close the PR without merging it.
+
 ## "Work In Progress" pull requests
 
-Marking a pull request as being a work in progress will prevent that pull request from being accidentally merged. To mark a pull request as being a work in progress, you must prefix its title by `WIP:` or `[WIP]` (case insensitive). Those values are configurable in your `app.ini` file :
+Marking a pull request as being a work in progress will prevent that pull request from being accidentally merged.
+To mark a pull request as being a work in progress, you must prefix its title by `WIP:` or `[WIP]` (case insensitive).
+Those values are configurable in your `app.ini` file:
 
 ```ini
 [repository.pull-request]