Hi Arturo,
Thanks for contacting us.
You don’t need to enter the API key for this plugin to work, as here you can set pointer by giving latitude and longitude or by address. For example you can use the following shortcode to show New York on google map
[ebs_googlemap width="false" height="400" latitude="0" longitude="0" address="New York" zoom="6" type="ROADMAP"]
Please feel free to contact us in case you have any further query.
Thanks