Add to that, for an extant installation I’d rec Incus for the VM work with its web-ui. You get to keep your kernel, you’re less tied at the hip to it.

2 port Intel NIC + some switch and your server is a router too. Opnsense’s web ui is great, can be difficult to find stuff but searching gets you there, but most is easy enough and it’s the best web ui + automatic updates for routers out there.