JSFiddle - React, Tailwind, and code Playground

HTML

<div id="map-canvas"></div>


<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>

CSS

html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}
p,h4 {
    margin:0;
}
#map-canvas{
    width:425px;
    height:300px;
    margin:1em;
}

JavaScript

function initialize() {
    var myLatlng = new google.maps.LatLng(-38.06794990,145.30192430);
    var mapOptions = {
        zoom: 4,
        center: myLatlng,
        mapTypeId: google.maps.MapTypeId.ROADMAP
    }

    var map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);

    var contentString = '<div style="width:300px;"><H4>Heading</H4><P><B>Address:</B> Community Centre 51L The Strand, Narre Warren South 3805</P></div>';

    var infowindow = new google.maps.InfoWindow({
        content: contentString
    });
    
    var marker = new google.maps.Marker({
        position: myLatlng,
        map: map,
        title: 'Food Waste and Organics workshop'
    });
    infowindow.open(map, marker);
    
    google.maps.event.addListener(marker, 'click', function(event) {
        infowindow.open(map, marker);
    });
    
     google.maps.event.addListenerOnce(map, 'idle', function(){
      //google.maps.event.trigger(marker,'click');
 });     
}
google.maps.event.addDomListener(window, 'load', initialize);