In some fanfics, Naruto may move out of his family to pursue a particular training or a mission that his family doesn't support. For example, if his family has a traditional view of ninjutsu training and he wants to explore a new, unorthodox style, he may choose to leave to follow his passion without their interference. He might also move out if he discovers a secret about his family that makes him feel uncomfortable or betrayed, and he needs space to figure things out.
One reason could be that he wants to seek independence. Naruto has always been a bit of an outcast in his family, and he might feel that moving out is a way to prove himself and grow on his own. He could also be tired of the family drama or conflicts that might exist within the family unit in the fanfic.
Maybe he wants more independence. In many fanfics, characters like Harry might feel restricted at home and long for the freedom to make their own choices, so that could be a reason for him to move out.
In some fanfics, Naruto might leave his family because of a dangerous threat approaching them. He could believe that by leaving, he would draw the danger away and keep his family safe.
It could be that Naruto discovers some secrets within his family that make him feel uncomfortable or out of place. For example, if there are hidden agendas or dark pasts that he doesn't want to be associated with, he might choose to move away to start anew.
It could also be due to power struggles within the family. Naruto's growing power might threaten the existing power balance in the family. Some family members, fearing a loss of their influence, decide to reject Naruto to try and keep their power. For instance, if Naruto has a unique ability that could potentially change the family's long - established ways of doing things.
He could be influenced by a powerful and mysterious force. This force might be something magical or a very strong jutsu that causes him to lose his memory and wander away from his family. In some fanfics, new and made - up powers can often play a role in such situations. Without his memory, he doesn't recognize his family and just drifts away.
It could also be due to a lack of support. Naruto was constantly in trouble and trying to prove himself. If his family didn't show up in any way to support him and Konoha didn't do enough to encourage him in a positive way, but rather just punished him for his pranks, he might grow to hate them both.
One possible reason could be some kind of dark magic or jutsu that has affected his family's memories. Maybe an enemy cast a spell specifically to make his family forget about him to weaken him.
One possible reason could be that he feels neglected. Maybe his family was always too busy with other things and didn't give him enough attention. This lack of attention during his formative years could have led to feelings of resentment.
It could also be related to external forces. Maybe an enemy of the family or the village plants false evidence that makes Naruto seem like a danger. Since he is 'godlike', the family might believe the false accusations more easily, fearing his power, and expel him. Also, there could be a power struggle within the family, and those in power see Naruto's 'godlike' nature as a threat to their authority and use some excuse to kick him out.
He could be running away because of false accusations within the family. Just like how he was wrongly judged by the village in the original story, if his family wrongly blames him for something he didn't do, like stealing a family heirloom or causing harm to a family member accidentally, he might choose to run away rather than face their unjust wrath.