How would you set this up? You'd still need a box with a public IP to proxy the traffic, no? (Unless you get all your friends to install Tailscale so that they can access your private network).
it/s called exit nodes in Tailscale
I don't think that would work? Exit nodes proxy traffic from the Tailscale network to the internet, not the other way around. Kind of like a consumer VPN.
The other reply mentions Funnel, which I think fits the use case better.
If you want to expose a single web service you can do it via tailscale funnel[1] easily.