Take creating a virtual machine in VirtualBox as an example: Launch VirtualBox and click the "New" icon in the top left corner of the window. In the Create Virtual Machine dialog box, type "Windows 10" and then click the “Version” to select OS version. Decide how much RAM you want to allocate for this VM. Select "Create a virtual hard drive now" and click “Create” to create a virtual drive. Decide the size of the virtual hard drive. Click “VDI” (VirtualBox Disk Image) as the file type for the drive and click “Next”. Choose “Fixed Size for the virtual drive” and click “Next” button.  Name the drive and confirm its size, and click “Create” to complete the process. Choose Windows 10 ISO files in VirtualBox to install it.