The easiest way to add a public holiday calendar is to set this up on your iCal and sync the holiday calendar with Cupla. Here's how:
Follow this guide to add the calendar to iCal: https://support.apple.com/en-nz/guide/calendar/iclead4e0ec3/mac
Open Cupla and tap More.
Tap Calendar Settings.
Tap Resync Calendars.
Tap Calendar Connections.
Scroll down to Holiday calendars and tick the box.
Tap Save.
You should now see the Holiday calendar in your Cupla calendar.
