Often, the hero in a sword novel is someone who overcomes great difficulties. Take Frodo from 'The Lord of the Rings' (although it's more of a ring - centered story with a lot of sword - related elements). He has to carry the heavy burden of the ring, face numerous threats, and still manages to be brave. His journey is full of challenges that he bravely endures, making him a marvelous hero in the context of a story with swords and battles.
I'm not sure specifically as there could be various novels related to Dragon Balls. Generally, it might be about the adventures of the characters in the Dragon Ball universe, their battles to collect the Dragon Balls, and the use of the wishes granted by the Dragon Balls. It could also involve the growth of the main characters like Goku in terms of their power and relationships.
It's completely fictional. The show's plot and characters were developed by the writers' imagination rather than being based on real-life events or people. But it still manages to capture the audience's attention with its charm and humor.