Шаблон: dropdown_menu_form.html
<form action="{% url 'dropdown_menu_form' %}" id="dropdown_menu_form">
<select name="dropdown_menu_option" form="dropdown_menu_form">
<option value="Att1">Att1</option>
<option value="Att2">Att2</option>
<option value="Att3">Ope3</option>
</select>
</form>
urls.py
path('dropdown_menu_form/', views.dropdown_menu_form, name='dropdown_menu_form')
views.py
def dropdown_menu_form(request):
if request.method == "POST":
selected_value = request.POST.get('dropdown_menu_option')
#do something
else :
template = 'app_name/dropdown_menu_form.html'
return render(request, template)