how to split the string in django template?
Split is a custom filter, don't forget to create your filter, and to load it in your HTML page. Documentation for Django 4.0: https://docs.djangoproject.com/en/4.0/howto/custom-template-tags/
<h4>Skills</h4>
{% with form.instance.skills|split:"," as skills %}
{% for skill in skills %}
{{ skill }}<br>
{% endfor %}
{% endwith %}
For extract character string, use filter cut:
<a href="tel://+1{{ phone|cut:'-' }}">Phone</a>
this removes the scripts from the string.