A customer need to perform some tests on a Windows 10 Home VM.
The first step is to decide which hypervisor your customer wishes to use. Popular choices include VMWare Workstation Player, Oracle Virtual Box, and Microsoft's own Hyper-V.
Having made that choice, the next step is to setup the software and create a virtual machine.
The last step is to install Windows in the virtual machine. Installing Windows in a virtual machine is the same as installing Windows in a physical computer because, for all intents and purposes, a virtual machine is just like a physical computer.
Keep in mind that Windows installed in a virtual machine needs to be activated, just like Windows in a physical machine. As a practical matter, however, if your customer is only going to be testing Windows for a short time, they can probably dispense with activation.