Is it possible to use an Azure Web Job to listen on a public socket

Can an Azure Web Job listen on a public TCP port (socket)

I am deploying a Web Application to Azure, and it has a long running Web Job that listens to a TCP port (a custom protocol is involved, so a raw socket is required)

The listener runs, but I want to send data from outside of Azure, from another on-prem machine.

The port is listening OK, it can open an incoming socket, but it is internal (10.0.X.X)

I suspect a public port like this is NOT possible, but I want to be 100% sure of that limitation, before I invest in an alternate solution.

FWIW, the protocol is for HL7

If it is not possible, would a point to point VPN into the Web Application be one option, to tunnel the connection from on-prem to the Web App?

Are there other approaches (maybe Azure Functions) that I should consider instead?