On-prem to cloud provider - networking and connectivity

I have a request to install Rancher server on-prem (basically inside lab with intranet) and then create kubernetes clusters on cloud like AWS. So basic question is how will bi-directional communication work, like how AWS user cluster communicate back into Rancher? what should i do on network layer to make it work? Is it a must that Rancher on-prem should have public IP?