Go go Confluence Administration Page, on left menu, click on Page View Configuration to go to Page View Configuration page
...
Get API key here https://developers.google.com/maps/documentation/javascript/get-api-key
and create Billing account here: https://developers.google.com/maps/gmp-get-started
a) Click on GET A KEY button to open a popup
...
Pageviews' location are getting via IP Geolocation API service. By default, we use https://reallyfreegeoip.org/json/, but use can use other services. For more information please read IP Geolocation API.
After setting successfully, you can view the map by clicking on map icon 
in Page Views Statistics page, map will be display like below:
