Hi nauna,

To get the GPS location you need use navigator.geolocation property and getCurrentPosition returns the Latitude and Longitude value.

For more details refer below article.

Get Current Location Latitude and Longitude using JavaScript and HTML5

For refreshing every 5 or 10 second you need to use JavaScript setInterval function.

Refer below code.

HTML

<script type="text/javascript">
    window.onload = function () {
        setInterval(GetGPSData, 5000);
    };
    function GetGPSData() {
        if (navigator.geolocation) {
            navigator.geolocation.getCurrentPosition(function (p) {
                var LatLng = new google.maps.LatLng(p.coords.latitude, p.coords.longitude);
                var mapOptions = {
                    center: LatLng,
                    zoom: 13,
                    mapTypeId: google.maps.MapTypeId.ROADMAP
                };
                var map = new google.maps.Map(document.getElementById("dvMap"), mapOptions);
                var marker = new google.maps.Marker({
                    position: LatLng,
                    map: map,
                    title: "<div style = 'height:60px;width:200px'><b>Your location:</b><br />Latitude: " + p.coords.latitude + "<br />Longitude: " + p.coords.longitude + "</div>"
                });
                google.maps.event.addListener(marker, "click", function (e) {
                    var infoWindow = new google.maps.InfoWindow();
                    infoWindow.setContent(marker.title);
                    infoWindow.open(map, marker);
                });
                alert("Your location:\nLatitude: " + p.coords.latitude + "\nLongitude: " + p.coords.longitude);
            });
        } else {
            alert('Geo Location feature is not supported in this browser.');
        }
    }
</script>
<div id="dvMap" style="width: 500px; height: 500px">
</div>