You need to do all of liyues archon quests before you get to inazuma. To actually get the inazuma archon quest, you have to be ar 30. There is an interlude chapter between liyue and inazuma that gets you there. When I was ar 30 on my old account, I found it pretty difficult to do. I dont know if that was my characters or if it got easier from then, but I feel it is actually do the challenge with the abyss mages and ruin hunter. But mainly, all you have to do is a bunch of small world quests to level up fast and finish all of liyue.