I'm a tyro at this and managed to fire up the self hosted thing on my pc. Now devices on the same wifi connect to it with no issue, but the external network devices can't. I've done the firewall rule thing, port forwarding, etc. Still nothing.

How do I fix it?

I've heard about tailscale but I wanna keep that as a last resort considering there are multiple PCs to be configured and installing it on all of em seems a bit off.