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 %}