How do I make a GroundControl Software send something on UDP?

I am trying to implement this project: https://github.com/DroneBridge/ESP32
But I can’t connect any GroundControl Software to the ESP.

When trying UDP I get Mavlink Connecting... loading forever.
When trying TCP I get: No Hearteat Packets Received .

The guide says In case of a UDP connection the GCS must send at least one packet (e.g. MAVLink heart beat etc.) to the UDP port of the ESP32 to register as an end point.

Is this done automatically ? How do I do this ?