I want to make it 2 way sync, that is, whatever changes i made on google calendar will appear on rainlendar, and whatever changes i made on rainlendar will also appear on google calendar. Is this possible? If yes, how can i do it?
Do i have to get the pro version of rainlendar inorder to achieve this?

I searched the forum for similar topics, but i didnt find anything helpful. Maybe i didnt do it right? Any help will be appreciated.Thx~

It works by default that way. The events created in Rainlendar to the Google Calendar also appear there and all changes done in Google Calendar will appear in Rainlendar once they are read back from the Google's server. And yes, you need the Pro version for this.