The following Multisite screen will be seen if you have the Multisite Network setup activated. My Calendar > Settings > Multisite.

My Calendar > Settings > Multisite

Multisite configuration – input

Site owners may only post to their local calendar.
Site owners have access to post only to their own sub site calendar.

Site owners may only post to the central calendar.
Site owners can only post to the primary sub site calendar.

Site owners may manage either calendar.
Site owners can manage their own sub site and the primary (sub) site calendars.

Multisite configuration – output

Sub-site calendars show events from their local calendar.
Show events from only the sub site calendar.

Sub-site calendars show events from the central calendar.
Show events from the primary sub site calendar.