Can I just get on and ride?
Watopia and Richmond today, but it looks like the NY course and Watopia for the next few days: https://zwiftinsider.com/schedule/
Ok. Thanks. no way to just set up as a stand-alone course?
You can still use the World Tag Hack to ride any course you want.
From Zwiftinsider.com (Link): Does the tried and true world hack still work in this new Guest World system? Yes! Whatever world you hack into will replace Watopia on the World Choice menu.
How do I do that - on Apple TV?
As far as I know there is no way to World Hack an Apple TV, you will have to ride what is on the schedule.
OK - thank you again.