IP white lists and firewall exceptions will help, but exposing ports on your home router is almost always a bad idea, especially for something as trivial as a game server.

I would highly recommend Tailscale. It’s free for up to 3 users, and if you have more friends than that, I would have them all sign up with free accounts and then share your laptop device with their tailnets.

It’s very easy to setup and use, costs nothing, and will be far more secure than opening ports and trying to set up IP white lists, protocol limitations, etc.

Tailscale creates something called an “overlay network” it’s basically a virtual LAN that exists on top of your real network and can be extended to other people and devices over the internet. It’s fully encrypted, fast, and like I said, very easy to set up.