Building a High-throughput VPN
Create a VPC named cloud to simulate your Google Cloud network, and a VPC named on-prem (on-premises) to simulate an external network.
Create VPN gateways, forwarding rules, and addresses for the cloud VPC and Form a tunnel for the new VPN, and route traffic through it.
Repeat the VPN creation process for the on-prem VPC, creating a second VPN.