Converting a template to a virtual machine changes the template. This action does not make a copy. You convert a template to a virtual machine to edit the template. You might also convert a template to a virtual machine if you do not need to preserve it as a golden image for deploying virtual machines.
Verity that you have the following privileges:
Virtual machine .Provisioning.Mark as virtual machine on the source template.
Resource.Assign virtual machine to resource pool on the resource pool where the virtual machine will run.