Hi@akhtar,
It's correct that the network argument of the docker run command only supports one network. But we can connect another network card to our container.
Example:
create multiple networks
- docker network create --driver bridge net1
 
- docker network create --driver host net2
 
run the container using the initial network and connect it to the other network.
- docker run  -it --name Ubuntu --network net1 Ubuntu
 
- docker network connect net2 Ubuntu
 
Hope this will help you.
Thank You