How to make an error page?

Question

Django

how to create a page with an error display and so that it would be possible to return back

get_token:

def get_message_token(self) -> str:

""" Get message token from database """
        _name = "get_message_token"
        try:
            company_object = userModels.Company.objects.get(
                id=self.meeting["company"])
            token = models.MessageToken.objects.get(
                company=company_object).token
            libenv._debug(
                f"[*] {__name__}: {_name}: \
                    Company {company_object} assigned token: {token}")
            return token
        except models.MessageToken.DoesNotExist:
            token = models.MessageToken.objects.get(is_default=True).token
            libenv._debug(
                f"[*] {__name__}: {_name}: \
                    Default token assigned for \
                        {self.meeting['company']}: {token.token}")
            return token
        except Exception as e:
            raise e

views.py;

class GuestMeetingCreateView(LoginRequiredMixin, CreateView):
    model = models.Meeting
    form_class = forms.GuestMeetingForm
    template_name = "meeting/_form_add_participant.html"
    success_url = reverse_lazy("meeting:list")
    permission_required = "meeting.add_meeting"
    permission_denied_message = _("warning_message_no_add_permission")
    permission_denied_page = "base.html"

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        if hasattr(self, 'request'):
            kwargs.update({'user': self.request.user})
        return kwargs

    def form_valid(self, form):
        self.object = form.save(commit=False)
        self.object.company = self.request.user.company_id
        self.object.contact_person = self.request.user
        return super().form_valid(form)

    def get(self, request, *args, **kwargs):
        if request.user.has_perm(self.permission_required):
            return super().get(request, *args, **kwargs)
        else:
            return render(
                request,
                self.permission_denied_page,
                messages.warning(
                    request,
                    self.permission_denied_message
                )
            )

    def post(self, request, *args, **kwargs):
        if request.user.has_perm(self.permission_required):
            return super().post(request, *args, **kwargs)
        else:
            return render(
                request,
                self.permission_denied_page,
                messages.warning(
                    request,
                    self.permission_denied_message
                )
            )

forms.py;

class GuestMeetingForm(forms.ModelForm):
    """
        **Class representing web form
         with information from Meeting for Guest model.**
    """
    attendee = forms.ModelChoiceField(queryset=None, label=_("attendee"))

    class Meta:
        model = models.Meeting
       
    def save(self, commit: bool = True) -> Any:
        _name = 'save'
        meeting_object = super().save(commit=False)
        libenv._debug(f'[*] {__name__}: {_name}: {meeting_object}')
        if commit:
            numregGenerator = self.NumRegFactory(meeting_object)
            meeting_object.registration_number = numregGenerator.generate_registration_number(  # noqa: E501
                meeting_type=f"G{meeting_object.meeting_type}")
            meeting_object.save()
            self.create_nda(self.populate_nda(meeting_object.get_guest()))
        return meeting_object