And then do everyone else.
And then do yourself.
And then do it all over again.
Like ten more times.
So who are these three girls in the closing credits?
Noelle, Mimosa, and the dark-haired girl they meet on the beach at the end of the episode. It looks like the artwork reimagines them with modern-day high school uniform outfits. Naruto's done that before. Like re-imagining them as like slice of life anime high schoolers in Japan. Same concept here.
Dark haired girl is Kahono, a priestess from the underwater temple where they are trying to go.