We connect the device to a back usb port of type usb2 (not usb3) on the Server PC

We connect to the Windows virtual machine through proxmox web interface (not from a client PC).

We login with a user with administrator permissions and we shutdown Windows virtual machine. On Proxmox on the left pane the virtual machine icon should be greyed.

We click on the virtual machine to select it. On the central pane we click on Hardware, then on Add button and we select Usb Device

We select Use USB Vendor/Device ID, click on Choose Device and select from the list, based on the manufacturer, the right usb device we have connected..

The usb id will be shown. We click on Add

We start Windows virtual machine. Usb connection has now passed through from the baremetal device to the Windows virtual machine. We can proceed to next actions like installing drivers etc.