how can I create a new Shared Network

Hello,
Thank you for your post.
Unfortunately, you can only have one Shared Network on the Mac.
But you have the ability to create multiple host-only networks.

This can be done by Right-clicking the Parallels Desktop icon > Preferences > Network > Click the '+' > This will create a new Host-Only network which can be used for internal use for virtual machines, but they will not have internet access.

Hence you can add 2 Network adapter to a VM, one will be a Bridged or Shared adapter so that the virtual machine has internet connectivity and another host-only if you want to.

Since the above might not actually be what you want to do, hence we would like to know more about your use case and why the ability to add an additional Shared network will be useful in your set-up, please provide as much information as possible.

Kind Regards,
Parallels Team