Sasuke would be more cynical about it. He might think Naruto is being foolish or overly dramatic. But at the same time, he would be curious about Naruto's motives. And if there are any threats involved that could endanger the village or their friends, Sasuke would reluctantly get involved to help Naruto.
Sakura would be extremely angry at first. She has known Naruto for a long time and would feel betrayed that he didn't trust her enough to tell the truth. But later, she would understand his reasons and might even help him if she could.
Hinata would be heartbroken. She loves Naruto deeply. However, she is also a strong - willed woman. She would start to suspect that something is wrong and might start her own investigation to find out the truth behind Naruto's 'death'. And when she discovers the truth, she would support him no matter what.
One possible reason could be to protect his family. After the war, Naruto might have made many enemies. By faking his death, he could draw the attention of these enemies away from his family, especially his wife and children. His enemies would think he's no longer a threat and stop targeting his loved ones.
Sasuke would likely be conflicted. On one hand, he and Naruto have a deep bond, but on the other, Sasuke has his own ideas about justice. He might try to stop Naruto at first, reasoning with him. If that fails, he could be forced to choose a side, either to support Naruto's cause if he believes there's some merit to it, or oppose him to protect the shinobi world as he knows it.
Sakura would be devastated. She has known Naruto for a long time and has seen him grow from a loud - mouthed kid to a great ninja. His death would make her question everything. She might become more withdrawn and serious. Hinata would be heartbroken. She had deep feelings for Naruto. She might even lose her will to fight for a while.
One consequence could be that his friends are devastated at first. They might go through a period of grief and self - blame for not being able to protect him.
Sasuke, on the other hand, might act like he doesn't care much on the surface, but deep down he would be a bit confused and might start to see Naruto in a new light. He's not very good at expressing emotions, so his reaction would be more subdued.
Iruka would be inconsolable. He was like a father figure to Naruto in the early days. His death on his birthday would bring back all the memories of Naruto's growth and how far he had come. The village as a whole would go into mourning. Naruto was the hero who saved them multiple times. There would be a sense of hopelessness among the villagers, and they would struggle to find a new source of inspiration without Naruto around.
Naruto could also be defiant. Given his strong - willed nature, he might not accept the banishment quietly. He may try to prove his innocence or the importance of his presence in the village. He could use his godlike powers to make a statement, not in a harmful way, but to show that banishing him is a mistake. For example, he might perform some great feats to protect the village from an outside threat even while banished, to show that he still cares about it.
Sasuke would likely be initially suspicious of the Death Korps of Krieg. He's always been cautious around new and potentially powerful forces. However, he would also be intrigued by their military might and might seek to learn from them to further his own power.
For Ron and Hermione, they would likely be devastated at first, thinking they had lost their best friend. But then they might start to suspect something when they notice small details that don't add up. Ginny would be heartbroken and might become more determined to fight against Voldemort in revenge. The Order of the Phoenix would be in chaos, with some members losing hope while others might start to investigate the circumstances of his 'death' more closely.
Well, it would probably shock everyone. Sasuke might feel betrayed as Naruto is his closest friend. For Boruto, it could be a huge turning point. He might start to question a lot of things and feel the need to step up more. His relationship with his friends and family could also change as he tries to deal with the fact that his father is 'dead'.