Created announcement-edit.html file and added contents

widget_CtrlF/announcement_board/templates/announcements/announcement-edit.html

+{% extends 'base.html' %}
+{% load static %}
+
+{% block page-title %}Edit Announcement{% endblock %}
+
+{% block heading %}<h1>Edit announcement:</h1>{% endblock %}
+
+{% block content %}
+<form method="post">
+    {% csrf_token %}
+    <table>
+    {{ form.as_table }}
+    </table><br><br>
+    <input class="button" type="submit" value="Save Changes to Announcement">
+</form>
+{% endblock %}
\ No newline at end of file