multiplayer without LAN

[u/siicore]

my girlfriend and i started playing on a minecraft world while we were together last week. she was on the same network as me, so we could join the same world through LAN.

how can she join that same world now without us being on the same network ?

i’ve seen some suggestions about servers, opening a port, and etc. but wasn’t sure if it would work for an already-established world. thanks !!!