Check out example codes for "add a google calendar to mac calendar". It will help you in understanding the concepts better.

Code Example 1

#First you have to add new calender basically by adding google acount
#To "Change/add which calendars get synced"
#go to:
https://www.google.com/calendar/syncselect
and check the desired calender

Learn ReactJs, React Native from akashmittal.com