You going to need a plug-in to fix it back to the old fishing, but idk if you're willing to do that because it's a vanilla world. If you do want to do it, though, just look up how it up on yt there's a full tutorial their. Hope it helps 👍
watching the vid now but I THINK (dont quote me) glow squids only spawn at certain y levels so it might have be built underground and also they did change fishing mechanics and the pool has to be bigger for u to get enchanting books edit yep looked it up has to be below y level 30