Is ther a notification feature?
Get a notification from Teams when you have a message waiting.
Anthony Crain commented
There are multiple notification options. You can get an email. You can get a red dot on your banner or rail. You can get a pop up window on your computer. If you have the app you can get an app alert. By default you should be getting alerts without setting anything up. Then you can determine just what sort of thing should alert you.