how can i get the apple tv app on mac

I have an iMac Retina running Mac OS Mojave (I prefer not to upgrade at this time to the Catalina).

I don't have an 'Apple TV' but I recently bought a new iPad so I got the complimentary 1 year subscription to Apple TV+

How can I watch Apple TV+ on my Mac pc? I cannot find any TV app in my Applications folder and I can't see any way to download it from the App Store.