This article explains how to connect and configure a PS4 controller to Steam, and how to navigate Steam using the controller.
How to Connect Your PS4 Controller to STEAM on PC – Steam Desktop Update 2023
Before you start using your PS4 controller with Steam, there are a few preliminary steps you should take, including making sure you have the latest version of the Steam client. Follow these steps:
Open Steam and connect your PS4 controller to a USB port on your PC.
In the Steam client window, select Display > Settings > Controller > Global Controller Settings.