Package name    : AEM
Iflow name      : Publish_to_Queue
Sender http path: /Publish_to_Queue

1) Add Request-Reply with adapter type 'AdvancedEventMesh'

2) At 'Connection' tab, enter:
a) Host
b) Message VPN
c) Username
d) Password Secure Alias

3) Add Secure Parameter (store password only)

4) At 'Processing' tab, enter:
Delivery Mode    : Persistent (Guaranteed)
Endpoint Type    : Queue
Destination Name : qFirst

5) Create queue qFirst in event broker.

6) Postman send message to iFlow, publish to qFirst.

7) Change to dynamic queue name ${header.qName} pass from Postman's header

8) Create queue qSecond in event broker.

9) In postman, set header qName = qSecond, then send message to iFlow, publish to qSecond.

Reference:
https://help.sap.com/docs/integration-suite/sap-integration-suite/configure-advanced-event-mesh-receiver-adapter