Streaming WGN news

The Apple TV app on your third party streaming device offers you access to:

• iTunes Store movies and TV shows (buy or rent);
• Apple TV+ channel featuring Apple Originals [1] [2], by subscription;
• select other premium Apple TV app Channels, each by subscription.

not other services.

The Apple TV app on your third party streaming device doesn’t support the installation of apps for the Apple TV box. It doesn’t work that way. Instead, install apps as offered by the device manufacturer from their app store.

Alternatively, you may be able to stream using AirPlay from iPhone or iPad to an AirPlay-enabled smart TV.

WGN News Chicago app - App Store (iPone, iPad) preview - Apple

WGN-TV+ app - App Store (Apple TV box) preview - Apple

Use AirPlay to stream video or mirror the screen of your iPhone or iPad - Apple Support

If screen mirroring or streaming isn't working on your AirPlay-compatible device - Apple Support

Apple TV app vs. Apple TV box - Apple Community

they seem to have an app for appletv WGN-TV + on the App Store (apple.com)

and another which is only for other ios devices WGN News - Chicago on the App Store (apple.com)

if you have an older appletv without app store like 1g, 2g, 3g then you are out of luck

if the tv+ app is not what you are looking for then you need to contact wgn and try to convince them to make an appletv app too

How to contact an app developer - Apple Support

or if the apps on ipad and iphone allow it then you can airplay mirror it to the appletv