How to connect my google calender with CRM?

How to connect my google calender with CRM?

Hi guys, 

We serve more than 200 customers and engage with them periodically. Sometimes one of my colleagues may forget to interact with them so it would cause a disappointment in my customer. I would like to connect my Google Calendar and integrate it with CRM so I can monitor the activities of that particular account. 

I would like to assess which accounts I have not reached out etc. How can I do that? 

We're using Google G Suite.