How to add Google maps on Contact us page using javascript.

<link href="/maps/documentation/

javascript/examples/default.css" rel="stylesheet">
    <script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>
    <script>
function initialize() {
        var myOptions = {
                zoom: 14,
                center: new google.maps.LatLng(26.89730702598253,80.95929462695312),
                mapTypeId: google.maps.MapTypeId.ROADMAP
              };

              var map = new google.maps.Map(document.getElementById('map_canvas'),
                  myOptions);

              /*var marker = new google.maps.Marker({
                position: map.getCenter(),
                map: map,
                title:'Lekhraj Panna Bus Stop, Sector 2, Vikas Nagar, Lucknow, Uttar Pradesh 226022, India'
              });*/
           
    var infowindow = new google.maps.InfoWindow({
    });

    var marker = new google.maps.Marker({
                position: map.getCenter(),
                map: map,
                title:'Lucknow'
              });

    google.maps.event.addListener(marker, 'click', function() {
        infowindow.setContent('<h4>Lucknow India</h4><p>Lekhraj Panna Bus Stop, <br>Sector 2, Vikas Nagar, Lucknow,<br> Uttar Pradesh 226022, India</p><a href="#info.html">See info</a>');
        infowindow.open(map,marker);  
    });
  
              }
             
              google.maps.event.addDomListener(window, 'load', initialize);

    </script>