<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style>
        html, body {
            height: 100%;
            width: 100%;
            margin: 0;
            padding: 0;
        }

        #map {
            height: 100%;
            width: 100%;
        }
    </style>


</head>
<body>
    <div id="map"></div>
</body>

    <script>
      var map;
      function initMap() {
        map = new google.maps.Map(document.getElementById('map'), {
          center: {lat: 40.689104, lng: -74.044599},
          zoom: 16
        });
      }
    </script>
    <script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCJ9w3VZc4WsOhZ2wDBJIbKVaePc1SMG3E&callback=initMap"
    async defer></script>
</html>