Adding Post Processing to Unity
If you are reading this article the you are interested in adding a post processing stack to your Unity game. This article will show you had to add the post processing stack to Unity if you are using the Built-in Render Pipeline.
First it is important to understand that the Post Process Package available to you is dependent on your Unity projects Render Pipeline. Unity supports three and most default projects use the Built-in Renderer. This article wont talk about the Universal Render Pipeline (URP) or the High Definition Render Pipeline (HDRP) just know that when you start a project using one of those pipelines your Post Process Package is already in the project.
The Built-in pipeline does not come with Post Processing by default. We need to install it using the package manager by clicking Window > Package Manager.
When you open the package manager you will get the window you see below. It will likely default to the Project Packages, which is a list of current packages you have installed in your game. You can think of packages as extensions to the Unity engine, give you access to other tools you might only need for some projects. You can change the default list of packages in the window by clicking the drop at the top of the package manager and choosing the one you want.