Use Hybrid Connection from onPrem to App Service

Hybrid Connections do not support initiating traffic from on‑premises to Azure App Service. They operate in a single direction, enabling an App Service to securely access a designated TCP endpoint within the on‑premises environment. The App Service itself is not exposed through the Hybrid Connection, meaning it cannot be directly reached, “pinged,” or connected to from on‑premises systems.

https://learn.microsoft.com/en-us/azure/app-service/app-service-hybrid-connections?tabs=windows

https://learn.microsoft.com/en-us/azure/azure-relay/relay-hybrid-connections-protocol