In the calendar you get two options, you can either use the 'Default Calendar' or if you want to add your own calendar click '+Add Calendar'
Menu >> Settings >> School >> Calendars
Menu >> School >> Calendars
If you like to add a calendar click '+Add Calendar' and a popup calendar setup page will appear.
Give a title or name to the calendar then, add desired data like - Creating your calendar duration years, Weekdays Setup, and choose who will be able to see the events in the calendar of the particular year.
Title > Start and End date (from, to) > Weekdays selection > Select event visible to > Submit
To Add a New Event / Holiday click on the required date. An 'Add New' pop-up will appear. Here you select Event and Holidays from the options that are shown below.
At the Event Tab -
Calendar >> Click on date to add event >> Add event and details >> Submit
Similarly with the 'Holiday' section -