Naruto might be extremely heartbroken. He has always looked up to his mother, and being disowned by her would be a huge blow. He could become withdrawn and start to question his own worth.
He may also try to prove himself. Naruto is a determined character. So, he would likely set out on a journey to find out the truth or to change Kushina's mind. He might go on difficult missions, learn new jutsu, and show everyone, especially Kushina, that he is not what she thinks he is.
It could also be due to some external influence. Perhaps an enemy used some kind of mind - control or manipulation on Kushina. They made her think that Naruto was a threat, so she decided to disown him. In the Naruto universe, there are many powerful villains who could potentially do this kind of thing.
Kushina would be extremely worried. She would rush to Naruto's side immediately and start using her medical knowledge or any available resources to help him get better.
As he grows up, Naruto could become very angry. He might develop a sense of abandonment and this could fuel his determination to become stronger. He would want to prove himself to his mother, wherever she is. In this fanfiction, his anger could be a driving force in his character development.
Naruto's reaction could be complex. On one hand, he would be extremely excited. But on the other hand, he would be worried about the consequences. He has learned about the balance of the ninja world and might be afraid that bringing Kushina back could have negative impacts. However, his love for his mother would probably overpower those concerns in the end, and he would still strive to make her return a reality.
Naruto would probably be really confused at first. He's used to a loving mother figure, not a yandere one. He might try to talk to her and understand why she's acting so strangely.
At first, Naruto might be extremely confused. He has always considered the village his home and Kushina as someone important. So being banished by her would leave him feeling lost and not understanding why it happened.
Naruto might initially be in shock. He has always counted on Kushina's love, and this sudden abandonment would be a huge blow. He could become withdrawn and quiet, not understanding why his mother would do such a thing.
In some cases, Naruto might initially become bitter towards his parents. But as he experiences more in life and learns about the possible reasons behind their actions, he could come to understand and even forgive them. His reaction would also depend on the people around him. If he has good friends or mentors, they could help him deal with his emotions in a more positive way.
Naruto would probably be very confused at first. Kushina is his mother, so her hurting him would go against his understanding of their relationship. He might initially try to talk to her, to find out what's wrong and if there's a way to fix it.
At first, Naruto would be shocked and confused. His world view would be shattered. But then, he would draw on his inner strength. He has overcome so many hardships before. He might feel a deep sadness, but also a sense of resolve. He would still believe in the power of love and friendship, and use that to face Kushina's betrayal. He could also use this experience to grow even stronger and more determined to prove himself and his beliefs.