Website calendar sync with Outlook and Google Calendar?

Question

Google

Good afternoon,
The service has a calendar in which all kinds of events are uploaded.
The task is to synchronize these events with Outlook and Google Calendar, when events occur or according to a schedule. In which direction to look for technology that will allow this to be done. It is necessary that the user passes authorization once, and based on this authorization, the service could create events in his calendar.
Thank you!

Answer 1

Use API
for Google - https://developers.google.com/google-apps/calendar/
for Outlook - https://msdn.microsoft.com/office/office365/APi/ca...