We are developing a rogulike, Hack & Slash RPG on Unity. Tell me, please, what technology options can I use for network multiplayer? Players will be able to simultaneously control their characters in real time. :)
You could try to use Photon Network and its PUN 2 version. You can use it for free if there is less than 20 players in the same time in your game, then you need to pay.
You can check their website: https://doc-api.photonengine.com/en/pun/v2/index.html
Or try to use this good tutorial: https://www.raywenderlich.com/1142814-introduction-to-multiplayer-games-with-unity-and-photon
It is globally simple to use but not trivial, so don't hesitate to create new ticket if you encounter new issues.