If you want to access the file uri in the node you have to iterate over the field in the node:
{% for image in node.field_image %}
{% if loop.first %}
<div class="class1">
<img src="{{ file_url(image.entity.fileuri) }}" />
<div></div>
{% else %}
<div class="class2">
<img src="{{ file_url(image.entity.fileuri) }}">" />
</div>
{% endif %}
{% endfor %}