ACF Google Maps - Google Map API Key Integration
In order to use ACF Google Map widget, you must first register a valid API key. To obtain an API key, please follow Google’s Get an API Key instructions.
The Google Maps field requires the following APIs: Maps JavaScript API, Geocoding API and Places API. You can then insert your API on our widget settings.
ACF Integration (Dynamic Mode)
So you will be able to check " Set this API also in ACF Configuration" only if you have ACF plugin activated and DCE will do the work for you.
ACF Integration (Manual Mode)
ACF requires Google Map API to be manually configured as described by the plugin in this documentation page.
Add this code in the function.php file of your theme-child. Follow the instructions on this page:
https://www.advancedcustomfields.com/resources/google-map/
function my_acf_google_map_api( $api ){
$api['key'] = 'xxx';
return $api; }
add_filter('acf/fields/google_map/api', 'my_acf_google_map_api');