Can't find way to the place i wanna go

Hi. I play not in English so I'll give things my own names. So:

I found camp of that guy from "foggy root planet". He said he knows how to go to the heart of "water tornado planet": I need to go to the tail of scary fish's skeleton, then find this guy's broken ship on the "long hollow root", then what?

I made my way inside that "long hollow root" and i came to the "orange glow sea creature" on the same planet. But i saw these creatures right under huge water flow that doesnt allows me to go deeper.

Then i tried to somehow interact with those orange creatures in water planet. It didnt helped.

Nothing more that i found. I have no idea How to get to the heart of "water planet"? Where should i go from broken ship of that guy from "foggy planet"? Thank you!