I have no clear idea. It could potentially be a comic adaptation in a different language or style of the Naruto story. But without more details, it's difficult to provide a definite answer.
Their relationship could be developed through a series of flashbacks. For instance, Itachi could recall moments from Naruto's childhood that he observed while in the ANBU. These memories could make him see Naruto in a new light. Meanwhile, Naruto could learn about Itachi's past and the sacrifices he made. This exchange of knowledge could build a bond between them based on empathy and respect. In addition, they could train together in secret, with Itachi teaching Naruto some of his ANBU skills, which would also strengthen their relationship.
Naruto would adapt to Itachi's life in several ways. Socially, he'd have to get used to Itachi's connections and rivalries. For instance, his relationship with Kisame would be different as Naruto. He might try to influence Kisame in a more positive way. Emotionally, he'd have to deal with Itachi's internal struggles. Itachi had a lot of guilt and secrets, and Naruto would have to either come to terms with them or find a way to resolve them. And in terms of combat, he'd practice Itachi's signature moves over and over to make sure he could use them effectively in battle.
They could develop a mentor - mentee relationship. Itachi uses his knowledge of the Sharingan to teach Naruto new combat techniques. As they train together, they bond over their shared experiences of loss and their desire to protect the people they care about. Naruto might also help Itachi come to terms with his past actions and find some peace within himself.
Itachi's protectiveness can make Naruto more confident. Knowing that someone as powerful as Itachi has his back gives Naruto a sense of security. This allows him to take more risks in his training and battles, which in turn helps him grow stronger. For example, he might attempt more difficult jutsu without fearing too much about the consequences of failure because he believes Itachi will step in if things go really wrong.
Well, in fanfic, a female Itachi could bring a whole new dynamic to the Naruto universe. Her character might have some of the same traits as the male Itachi, like being highly intelligent and powerful. But as a female, she could also have different relationships with other characters. For Naruto, this could mean a different kind of mentorship or friendship. Maybe she could guide Naruto in understanding the Uchiha clan better, which could be really interesting.
One possible fanfic could focus on a unique friendship between Naruto and a female Itachi. Maybe they meet in an alternate universe where Itachi was born female. They could start by being wary of each other due to their different backgrounds. Naruto, with his sunny personality, might gradually break through Itachi's reserved exterior, leading to a strong bond of trust and mutual understanding.
In many Naruto fanfictions, the ages of Naruto and Itachi can be quite flexible. Sometimes, authors might change their ages to create different story dynamics. For example, an author could make Itachi younger to explore a different version of his character development, perhaps showing him still in the early stages of his ninja training while dealing with the dark secrets of the Uchiha clan. Naruto's age might also be adjusted, like making him older to be in a more equal power dynamic with Itachi from the start.
Another teammate often included in fanfiction is Kakashi. Some fanfictions might create scenarios where Itachi and Kakashi interact during missions or even in their off - time. It could be interesting to see how their different skills and personalities clash or complement each other. For example, Kakashi's laid - back attitude contrasted with Itachi's more serious and reserved nature.