[Answer]-The submit button in a form doesn't work

Your markup is wrong, you aren’t closing the action attr:

<form  method='post' action='/new__categoryRequest>{% csrf_token %}
{{form}}
<p><input class='btn' type='submit' value='Add'/></p>

Shoud be this:

<form  method='post' action='/new__categoryRequest'>{% csrf_token %}
{{form}}
<p><input class='btn' type='submit' value='Add'/></p>