Well, the PC at home is behind a router, my router, unless it’s already being configured using the nice new firewall protocols, it will not actually have many holes in it. I will want to check, a few online checkers do exist. I’m building a kind of IOT thingy, so it possibly deserves a separate question really. Right now I’m connecting using a completely inappropriate secure-relaying non-vpn solution. Which is not terribly “open”.
I made a new thread instead @mike_123 : IOT thingy type home hosting