If you're getting messages that apps won't run unless Google Play Services is updated and you don't have a Google account set up on your device, then you can download & install the update for your version operating system that's on your android tv box. Please note that the Google Play Services apk's uploaded here are for the android tv box version ( armeabi-v7a/nodpi ). Do not install on any other type of device or you may encounter issues. There are no Google Play Service files for 7.1.2+ Nougat. You can install the 6.0 Marshmallow version that will also cover the update for the 7.0-7.1.2 versions.
Please note that some (not all) of the newer 8.1 - 10.0 TV Boxes have the ability to update Google Services automatically or manually. Check by clicking on the Google Play Store to see if a update notification is available.