What are your expectations? The Apple TV box is just using the TV as a monitor, and it does not take much effort to set it up. The TV just needs an HDMI port to plug the Apple TV box in and of course the box needs power. There are only 2 models being sold and for most the lower tier one for $129 is just fine. The other model for $149 has these additional features:
- Ethernet Connectivity
- Double storage from 64GB to 128GB
For additional information on the Apple TV, the User Guide is available here:
Apple TV User Guide - Apple Support
Setup Guide is here. Note that a 4K TV is not required and it does not turn a standard HD TV into a 4K TV, but it must be at least an HD TV.
Set up Apple TV - Apple Support
The difference between the 2 models being sold is here:
Apple TV 4K - Technical Specifications - Apple