<form action="{% url 'cv' format_= ... %}" method="post">
<fieldset>
<select class="form-control mx-auto" name="format">
<option value="docx">DOCX</option>
<option value="json">JSON</option>
<option value="html">HTML</option>
</select>
</fieldset>
<input type="submit" value="Download" />
</form>
{% for skill in user.employee.employee_skills.all %}