Is there a virtual PC that is recommended for iMAC?

What do you mean by "virtual PC"?

You can run Windows in a virtual machine like Parallels, Fusion, or VirtualBox. Or you can run Windows using Boot Camp Assistant.

Please provide more information regarding what it is you are trying to accomplish.

VirtualBox (from Oracle via its Sun acquisition) is free, but it is also the least user friendly to setup. But as far as I know it is a stable product (you cannot say that about all free products)

Parallels main business is the Mac, so their focus very Mac specific.

VMware's main business is data center virtualization, and VMware Fusion is not the center of their world. That does not mean the engineers working on VMware Fusion are not dedicated, but their product will not make or break VMware.

That is my 2 cents on the macOS 3 virtual machine products.

There's a few, paid and free.

Parallels: https://www.parallels.com

VMware: https://www.vmware.com

VirtualBox: hhttps://www.virtualbox.org

First of all i would like to know what will be your purpose for using the Virtual PC or Virtual Machine. There are couple of cloud PCs available in the market which can be used on Mac also like Microsoft windows virtual desktop, Parallels desktop or VMware

Then you will need to pay for a Windows 10 license, download the .iso Windows installer, and install it into any of the three virtual machines. Only Virtualbox is free. These are solutions that with sufficient RAM and available, fast storage — will allow you to run Windows 10 concurrently with macOS.

The other alternative is to use Apple's BootCamp (included with macOS) to add a new partition on the Mac boot drive, install Windows 10, Apple's tools for BootCamp into Windows 10, download your particular Windows-only application, and then you have a Mac that can you can boot either as macOS, or WIndows.

Check to see if the application you want to run will run under CrossOver

https://www.codeweavers.com/products

It is a paid product, but much less expensive than a Windows License and much less overhead on your Mac.

This assumes you just need to access a few Windows apps and CrossOver supports them, vs you need a full blown Windows environment.

If you need Windows, then one of the virtual machines mentioned will do that. Or of course if your app will not run under CrossOver.

I've been using Parallels for at least a decade, still use it but can't say what it's future is now that it's been sold to Corel. :(