It could involve elements like giving Naruto dragon-related powers or having him interact with dragons in a unique way.
Some fanfictions might draw inspiration from real-world issues and apply them to the dragon world, like themes of friendship and courage.
It could make you think about your own journey of growth and the obstacles you've overcome. Maybe the determination of the characters in the story mirrors your own when you strive for something you really want.
Honestly, there's not much of a direct relation. Maybe you could look at it from a perspective of fantastical creatures and spectacle, but even then, it's a loose connection at best.
Often, authors combine the powers and skills of Naruto characters with the dragons from How to Train Your Dragon to create unique storylines. Maybe a ninja discovers a hidden dragon village and forms bonds with the creatures.
It builds on the existing world and characters. Adds new adventures and plotlines that expand the 'How to Train Your Dragon' universe.
I have no idea. They seem like two completely unrelated things. How could they be connected?
Another aspect of the training could be mental discipline. Hayate may introduce Naruto to meditation - like techniques to help him focus his chakra more effectively. He'd also likely teach Naruto how to keep a calm head in the heat of battle, sharing his own experiences to illustrate the importance of mental fortitude.
It might introduce new elements or perspectives not present in the original. Fanfictions often take creative liberties to offer unique takes on the source material.
In the fanfic, Hiccup understands dragons through his close and empathetic interactions with them. He spends a lot of time observing and learning their behaviors.
In the fanfic, Mala might adopt Hiccup through a series of heartfelt and unexpected events. Maybe she sees his potential and kindness and decides to take him under her wing.