Can you provide instructions on how to do this please so I can provide to the family member who owns an apple device.
Like the support document says:
Set up Family Sharing - Apple Support
↳ Invite people to join the family
All the group members must each have a (complete and confirmed) Apple ID account, which defines the group. For those that don’t have such an account, one can be created.
↳ On the organizer’s iPhone, iPad, or iPod touch: see document
↳ Or: on the organizer’s Mac (macOS Catalina 10.15 or later, macOS Mojave 10.14 or earlier): see document
Once the invites have been accepted, the group setup is complete.
If you’re close by, then group members may join directly on the organizer’s device, instead of by message, if the organizer finds that easier: discussions.apple.com/thread/252739525.
All the group members should have device on which to watch Apple TV+. All the ways to watch Apple TV+ - Apple Support
(keeping in mind it is my subscription, not theirs). I imagine the steps are slightly different than if it's your own subscription you are setting up family sharing on (which Apple provide instructions on).
It makes no difference. Once the group is set up, any sharable subscription from any of the group members is automatically shared. You don’t have to (and can’t) specify to share Apple TV+. Each of the group members can access Apple TV+ subscription content as if they were subscribed themselves, each on their own account, even though only one of them has the subscription.
The optional sharing features are organizer’s choice, and may not be useful in your specific group (and can all be Off to just share Apple TV+).
