How to create an IVR has been covered at CSC hundreds and hundreds of times before, PLEASE search for answers before posting.
By default there's nothing you need to do, it will allow transfer, assuming you already have the CUCM-CUC integration, that's how call will be routed (assuming that's the configured behavior under transfer settings)
If you need further info on how to configure the call flow, or the call handler, search CSC and you'll find more than plenty information on previous posts.
HTH
java
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