A basic question about Fortigate lisence to cloud...

Hi all. We're migrating from on-premise to Azure.

We use Fortigate 400 series for VPN/firewall.

I saw Fortigate as SaaS on Azure marketplace, and there was BYOL option in adddition to subscription.

I was wondering, if we could use the hardware Fortigate lisence to Azure cloud.

Thank you for your help !