I can't get the first image to show on the homepage
Just a slight syntax issue it seems.

If you want just the first image - always test if there is an image, then get it like this:

{% if entry.galleryPhotos.first()|length %}
    {% set image = entry.galleryPhotos.first() %}`
    &lt;img src={{ image.url }} etc&gt;
{% endif %


Or if you want to loop over a few images...note here you don't need the |length test as the for loop will not be entered if there is no image:

{% for image in entry.galleryPhotos %}
    &lt;img src={{ image.url }} etc&gt;