By default, any Windows user with administrative privileges, i.e. a member of "Administrators" group, can manage the PVC server through CLI, PMC or PVA.
In Parallels Virtual Automation (PVA) it is possible to create users and assign certain roles to them.
We can create a user in and assign roles to manage your hardware nodes. You can find more details in the following articles:
Understanding Role-Based Access Administration in Parallels Virtual Automation
How to grant user with administrator access in PVA to particular virtual environments only