If the DN is a DID just configure a CTI RP with CFA to VM.
Otherwise once you get the call in CUCM do the same call flow (call forward to CTI RP with CFA to VM)
VM ports don need any special config other than be configured to take calls and make calls.
In CUC configure the call handler with the same DN as you get the call in CUCM, record greeting.
Configure caller input to attempt transfer to another call handler to create a submenu or a subscriber or whatever you need to do.
To reach a DN after caller input configure the caller options of the subscriber or call handler to "yes, ring subscriber at this DN"
This is not a queue so you don get MOH unless you configure a supervised transfer.
Examples, questions and howtos on creating an AA with CUCM/Unity/CUC have been answered PLENTY of times before, Id recommend you to search CSC before posting any new questions as most likely it has been asked before.
If this helps, please rate