I want to watch movies on my 4K Apple TV using the new AppleTV app, the movies reside in iTunes and that library is stored on my iMac’s internal HD. All the movies are in .M4v format. My question is, what steps do I need to take to watch these movies using the new Apple TV app on my 4K Apple TV? I also have the Apple TV app on my 2018 Samsung TV and would like to watch the same content there too. Thanks in advance!