So the ninja world is broken down in two ways. First of all it's not like the old system with the 5 villages from the series, instead it's called "The Warring States Era" (WSE). It's based on the time before the villages were formed and clans fought, like senju and uchiha.
So you can make your own clan with friends that then you can level up. The higher the rank your clan is, the more people you can have, the more landmarks you can claim. Nice way build something custom.
Step two is that we have arcs. This basically breaks down the ninja world story into chapters. New arcs like from 1-3 months and have a specific theme. The current one is that the world got red fever, people are dying, not staying dead etc. We need a cure. Bit reflective of RL right now.
The full version of the nw rules:
https://animebase.me/threads/ninja-world-rules-1st-year-anniversary-edition.767740/
All your stuff you have to do in character. It's a legit story mode. It takes 45 minutres to move from land mark to land mark. We even have an interactive map where you can see the world and click on any point to go to the thread for that landmark:
https://animebase.me/pages/map/
Any questions?