Not sure about the exact information you are looking for but creating a VM in hyper-v or in AWS is the exact same logic.
You may look if a PAM connector exists for a specific hypervisor or service. If not, webservices/API are always there. (Connector uses those ws/api by the way)
If you look for Hyper-V, System Center Virtual Machine Manager offers webservices. Manage Web Services and Connections in Service Provider Foundation
As per technet :
VMM web service
The VMM web service invokes System Center 2012 R2 Virtual Machine Manager to perform requested operations, such as creating virtual machines, virtual networks, user role definitions, and other fabric for the cloud.
If you look for VMware, there is an SDK for .NET. (Powershell / C# / VB.net). VMware vSphere Automation SDK Documentation
As per VMware doc :
The VMware vSphere Automation SDKs provide support for your client application infrastructure with services to perform management operations in your vSphere environment. The vSphere Automation SDK for .NET also contains samples that demonstrate how the libraries work with other vSphere APIs.
The version 6.5 SDK enables programmatic access to the following services:
- Service discovery using Lookup Service
- Authentication (Single Sign-On)
- Session management
- Tagging
- Content Library
- Virtual Machines
- vCenter Server Appliance management
Hope this helps