How to add to request field containing list of departments

How to add to request field containing list of departments

I want to create request to create user in AD and one of the fields should be with new user department  attribute (pickup list) but I cannot populate values from departments table. It would be perfect to notify manager of that department about that request after closing request.
Could you help me please?
                New to ADManager Plus?

                  New to ADSelfService Plus?