He bonds with tulkun outcast Payakan, who saves his life from a smaller sharklike creature when the reef divers abandon him outside the contained borders of their aquatic community.

Source: https://www.thewrap.com/avatar-the-way-of-water-cast-characters/

Loan’s bond with Payakan is never explained in Avatar: The Way of Waterand the sequel’s story isn’t negatively impacted by this lack of exposition.

Source: https://screenrant.com/avatar-3-jake-sully-main-character-kiri-replace/

Once Payakan lets his species know they need to fight or more of them will die, it's easy to envision the whales then trusting Ronal's tribe, buying into the concept.

Source: https://www.cbr.com/avatar-3-moby-dick-influence-whale-army/

Together, the children manage to free Payakan before he can be harmed, and he repays the favor ten-fold, by protecting the children from the submarines and the divers who follow them into the water.

Source: https://gamerant.com/avatar-will-payakan-earn-his-place-back-tulkun/

While not all of Avatar: The Way of Water, the movie’s refusal to explain Payakan and Lo’ak’s bond in literal terms reaffirms that there are parts of Pandora that even obsessive Avatar: The Way of Water fans can’t understand.

Source: https://screenrant.com/avatar-2-why-loak-tulkun-bond-not-explained/