You can read a list of calendars with getCalendarsAsync, and then read events from that calendar with getEventsAsync (see Calendar - Expo Documentation), but you cannot subscribe to changes on the calendar as they happen. You may be able to achieve a similar effect by re-reading the calendar whenever the app goes active (using AppState), or on a time interval.
Thank you for your reply!
Sorry, My description is too general, I mean, I want to create a subscription calendar, You know we can subscribe a calendar on iOS/Android through Url, I visit expo document, I know we can create a ordinary calendar by Calendar.createCalendarAsync, but I don’t know how to create a subscribe calendar.