<thead>
<tr>
<th>ID</th>
...
</tr>
</thead>
<tbody>
{% for user in users %}
<tr>
<td>{{ user.id }}</td>
...
<td>Удалить</td>
</tr>
{% endfor %}
</tbody>
<thead>
<tr>
<th>ID</th>
...
</tr>
</thead>
<tbody>
{% for user in users %}
<tr>
<td>{{ user.id }}</td>
...
<td><a href="/user/delete/{{ user.id }}">Удалить</a></td>
</tr>
{% endfor %}
</tbody>
@app.route('/user/delete/<int:id>')
def delete_user(id):
# # Здесь удаляете пользователя по id.
# User.query.filter_by(id=id).delete()
# db.session.commit()
...