purchased movie rental through Apple TV

Hi,

it is always best to rent it on your computer, and then transfer, because :

"If you rented the movie on your iOS device or Apple TV, you can’t move it to any other device."

About renting movies from the iTunes Store - Apple Support

But how do I do that? I've rented movies on my computer and I don't know how to connect my 4th generation Apple TV to the computer. The supplied USB cable does not fit on it (USB-C does not come in the box).

You'll need a USB-C to USB adapter to connect an Apple TV to a 12" MacBook

http://www.apple.com/shop/product/MJ1M2AM/A/usb-c-to-usb-adapter

I don't get why this cable is not supplied in the box.

Apart from that, this link you've sent is for for USB-C (male) to USB (female). Meaning that I would need an extra USB (male) to USB (male) cable, right?

You don't transfer content from your computer to the ATV using the cable. The cable is only used for diagnostic and troubleshooting purposes.

If you rent a movie from your computer, you can sync it to an iOS device and then use AirPlay to watch it on your ATV.

I think there's been some confusion.

The cable is only used for diagnostics, and to restore the Apple TV when necessary. You do not use it to transfer rented movies to the Apple TV. The Apple TV takes a Micro USB to USB cable. (different to USB-C) Only the 12" MacBook has a USB-C port.

To view a movie you rented on your computer on an Apple Tv, you can either use Airplay directly from the computer, or you can use HomeSharing.

Use Home Sharing to share iTunes content with other devices - Apple Support

The Rental should appear in the Rental Section of the Computers App and can be played from there.

Alternatively you can move the rental to an iPad, iPhone or iPod touch and Airplay it from there to the Apple Tv.

If you know you are going to watch in on an Apple TV rent it on the Apple TV. Otherwise rent it on a computer if you think you may need to move it to some other device or are unsure where you will watch it, or rent it directly on the device you intend to watch it on.