Communication with GCS to companion computer

Assalam O Alaikum Guys,
I was searching on how to communicate with onboard companion computer with GCS via telemetry. I found some solutions online but they are based on wifi. I was wondering is there any other way to do that like we can define target ID in mavlink message and its routed to the companion computer. likewise companion computer messages are routed to GCS. I have studied message routing but didn’t get the idea…
can anyone help me Please

May I ask which GCS did you use ?
Did you try RFD design radio modem ?