Invest in your characters. Trust me, though it sounds way too easy, it is not because you have to focus on meta and characters that can fit in that picture. The normal Genshin gameplay is focused on casual style, whereas things like the spiral abyss are focused on a competitive side of the game. Usually, when you are in the overworld, you are able to clear most of the challenges as they don't require you to do much on them. Even if an event needs you to face a challenging enemy, you can take help from your friends or randoms in a co-op mode. In the spiral abyss, you have to focus on teams that can output better damage to clear out waves of enemies in a time-limited frame and trigger reactions that can deal massive damage. Sometimes, there will be unique buffs for the characters of a certain element, and you can take the most benefit from it by using those characters. I should say that you should prioritize your resin usage on characters and try to invest in characters that have better meta potential. Characters like Bennett, Jean, Ganyu, Xingqiu, and Xiangling are a few meta characters that can help you in the spiral abyss. With constellations, your existing characters become more potent, and a good combination of characters in a team can help you nail any challenge in the game.