How to enable Taskbar auto-hide on Windows 11

To allow Windows 11 to hide the Taskbar automatically, use these steps:

Open Settings.
Click on Personalization.
Click the Taskbar page on the right side.

Quick note: You can always right-click the Taskbar and select the Taskbar settings option to access the settings page
Click the Taskbar behavior setting.
Check the Automatically hide the Taskbar option.

Once you complete the steps, the Taskbar will hide automatically when you move the mouse away from the element, giving you a little more real state to work with other applications.

Source - How to enable Taskbar auto-hide on Windows 11 | Windows Central