[packer] proxmox iso builder with uefi?

I’m trying to provision a Proxmox template using the Proxmox ISO builder, but the OS that I’m trying to provision only works with UEFI. Is there a way to change the VM BIOS in Proxmox to UEFI so the OS installer can boot?

When you create a virtual machine, you reach ‘System’ and you can choose OVMF (UEFI) in the BIOS section.
I’m not really sure how this is a packer question, though. This should have been posted on the proxmox forum.

As stated in the post, the provisioning ISO (the ISO that installs the OS) ONLY boots with UEFI. Because Packer creates the VM and then boots the ISO, the VM MUST be in UEFI before booting. Because Packer performs these actions in the process of creating a template, this is the appropriate forum (not the Proxmox forums) for the question stated: How can I have Packer set the VM BIOS to UEFI so the OS installer can boot?