There are a lot of ways to resurrect someone in-game, though I will not spoil any of the details here, there are players who has items that can perform resurrection, there are resources that lets you create your own, it can also be available as a reward from various quests, and lastly, there is also divine intervention, but this happens very rarely.
Several years ago we had an RPC whose role is solely to resurrect fallen characters, but the condition is that a player has to defeat its two guards from battles, but times have changed and the answers provided are the only ways so far.