Right now I don’t think you need to do anything special. Unless you did something out of the ordinary, Tailscale didn’t put your computers directly on the internet. What it did was create what’s called an overlay network that allows devices connected to that network to talk to each other. It’s private and encrypted and random folks on the internet can’t get on it by default.
Do learn some networking (there are tons of great YouTube channels, books, and podcast that can help), but right now you can afford to do that slowly and not try to rush to complicate your setup before you understand it. There’s so much material out there, but I found this particularly useful to get an overview when I was first learning: www.grc.com/sn/sn-309.pdf.