To get started, go to Window > Package Manager > Scroll until you find Post Processing. Install the package if it’s not already.
Create an empty Game Object in your hierarchy called Post Processing.
Within the empty game object go to add component > Post Process Volume.
Next, create a new layer name PostProcessing.
Finally, in your Main Camera go to add component > Post-Process Layer.
Set the layer to the one we just created, Post Processing.
Now you’ll be able to go into the Post Processing Game Object and change the values to do really cool things to your game scene and change it however you would like! Just like the scene I created as an example, the top is without post and the bottom is with. Enjoy!!