Hello legalbankr,
Family Share does not support sharing calendars, to my knowledge. You can share individual calendars with as many people as you want. Say you have a "Family" Calendar you add events too.
- Open Calendar
- Tap Calendars
- Tap the i icon next to one of the calendars
- Under Shared With, tap Add Person
Add as many people as you want. When you add an event to this calendar it will be shared with everyone that you shared it with - Share iCloud calendars on iPad - Apple Support. The steps above were for iPhone because I don't have an iPad🥲 This support page should help though!
If you need help setting up calendars, check out - Set up multiple calendars on iPad - Apple Support!
I hope this helps!