If Naruto was raised by his grandfather, he might have learned different jutsu earlier. His grandfather, with more life experience, could have trained him better. Also, Naruto's relationship with the village might be different. He might be more respected as his grandfather could have a certain standing in the village, and this could change how people view Naruto from the beginning.
It could be an old and powerful wizard who has been in hiding for years. Maybe he was a friend of Dumbledore's but had some differences with him, so he stayed away from the main events in Harry's life until now.
He could be a powerful and respected shinobi from the Uzumaki clan. Given the Uzumaki's reputation for strong chakra and unique abilities, Naruto's grandfather might have been a key figure in the clan's history.
One possible plot could be that his grandfather, perhaps a powerful but reclusive wizard, trains Harry in unique magic from a young age. Harry might grow up with a different set of values and skills compared to the original story. He could have a closer bond with the wizarding world's older traditions.
Harry could develop a more unique style of magic. His grandfather might have his own way of doing magic, and Harry would learn from that. For example, his grandfather could be more in tune with nature magic, and Harry would then incorporate that into his spell - casting, making his magic more diverse and less reliant on the traditional Hogwarts curriculum.
One possible plotline could be that Harry's grandfather imparts unique magical knowledge to him that he doesn't get at Hogwarts. Maybe it's an old - fashioned kind of magic that has been forgotten over time. This could give Harry an edge in dealing with the dark forces.
In this kind of fanfiction, Naruto might learn a lot of hidden family secrets. His grandfather could teach him some long - lost jutsu that was unique to their family. Maybe his grandfather would tell him stories about the early days of Konoha, which could give Naruto a new perspective on the village he loves so much.
Well, perhaps the grandfather could be teaching Harry all kinds of magic that his parents didn't have the chance to. He might introduce Harry to a different side of the wizarding world, full of old family secrets and forgotten spells.
The main character of the book "The Invincible Dragon God of the City" was a person named Ling Feng. When he was young, he was raised by his grandfather. Once, he was taken away by someone while playing. His code name was Long. I hope you like this fairy's recommendation. Muah ~๐