How to get rep with Nightfallen?

Could you please elaborate on the process of acquiring reputation, or "rep," with the Nightfallen faction in the game you're referring to? Are there specific quests or tasks that must be completed? Are there any daily or repeatable activities that can help boost your reputation status? Additionally, are there any rewards or benefits that come with having a higher reputation level with the Nightfallen? Understanding the specifics of this process would be greatly appreciated.