I would suggest looking up tailscales docs, its not massively complicated but I wouldn’t do the process justice.

But the short of it: signup with tailscale. Add tailscales software to each device. Then from tailscales admin panel go to setting, VPN, mullvad, setup payment then add up to 5 devices to use mullvad as an exit node.

Tailscale + mullvad integration works great if you want port forwarding and at about the same price as mullvad VPN.

Install size has gone up, its sluggish on my surface pro 7, its constantly wanting to grab my attention to put towards their other products, windows 10 was bad as it seemed to be ms’s first iteration of their now billboard, but at least I could offline install, make a local account and mostly be left alone. And windows 11 is aweful for its kiddy gloves.