How to customize the Google maps marker of Visual Composer?

I am using the latest version of the Visual Composer for wordpress on my site and I want to customize the standard red Google Maps markup.

I found this code on the Google developer site and I do not know how to use it with the Visual Composer.

function initMap() {
    var image = 'https://developers.google.com/maps/documentation/javascript/examples/full/images/beachflag.png';
    var beachMarker = new google.maps.Marker({
        map: map,
        icon: image
    });
}

I have looked for more information as a user suggests I have not been able to find anything neither the official site of Visual Composer, nor on the Google maps site.

link

In terms of code, I only use HTML and CSS, I'm learning a bit of JS but I'm still very raw, any information you can give me will be appreciated.

Good morning.