I own a mini pc with 4 ethernet ports and WiFi. I use QEMU/KVM for virtualization through virt-manager and somtimes I also use virsh command line interface.
To use the network ports from the VM, I add the hardware from the UI as given here:
Once it’s added, I update my /etc/network/interfaces with DHCP configuration:
allow-hotplug enp1s0
iface enp1s0 inet dhcp