You need to use DirectIP and Tailscale (modern version of hamachi if you're familiar with that)
the host will share his machine via tailscale and the other will join the tailscale network
the tailscale network will give an IP that the others can use to connect via DirectIP
the host will then host the server via direct IP and a port then share them to others
with this my friend are able to join and the connection is more stable and not lag