example-input.html

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<input name="address" id="input">
<script type="text/javascript">
$(document).ready(function() {
	getLocation();
});

function getLocation() {
	if (navigator.geolocation) {
		navigator.geolocation.getCurrentPosition(showPosition);
	}
	else {
		alert("Geolocation is not supported by this browser.");
	}
}

function showPosition(position) {
	// alert("Latitude: " + position.coords.latitude + "<br>Longitude: " + position.coords.longitude);
	var lat=position.coords.latitude;
	var lng=position.coords.longitude;
	var latlng=lat+","+lng;
	var apikey="*********";
	$.get("https://maps.googleapis.com/maps/api/geocode/json?latlng="+ latlng +"&sensor=true&key="+apikey, function(data, status) {
		// alert("Data: " + data + "\nStatus: " + status);
		var ADDRESS=data.results[0].formatted_address;
		$("#input").val(ADDRESS);
	});
}
</script>