virtual machines – How to modify a vᴍ instance setting to boot from BIOS to UEFI?

I shrank my boot hard disk size on my Google Cloud Compute ᴠᴍ. Something which switched the boot method of the ᴏꜱ installed on it from legacy to uefi along the disk boot’s settings (which triggers uefi setting must be the same for the instance and the boot disk. error).

How to change the Instance setting in order to match the (uefi) setting of the instance (given the ᴏꜱ boot method on the disk was migrated too) ?