In some fanfictions, Naruto might save Ino from Sakura if there's a situation where Sakura is, say, being overly aggressive or misdirected in her actions. For example, if Sakura accidentally uses a jutsu that endangers Ino during a training session, Naruto could use his quick reflexes and his own jutsu to block the attack and save Ino. Another possibility could be in a more complex plot where Sakura is under some sort of mind - control and Naruto has to step in to protect Ino from her.
One scenario could be a competition gone wrong. For instance, if there's a ninja skills competition between Ino and Sakura and Sakura cheats or loses her temper when losing to Ino. She might then try to attack Ino, and Naruto would save Ino. Another could be a love triangle - related situation. If Sakura thinks Ino is stealing Naruto's attention, she could lash out at Ino, only for Naruto to intervene.
Well, in the fanfiction, Naruto could save Ino from Sasuke by appealing to Sasuke's former friendship. Naruto might talk to Sasuke, reminding him of their days in Team 7 and how Ino is also their comrade, which makes Sasuke change his mind and let Ino go.
Simple. Naruto is a hero at heart. He can't stand seeing anyone being hurt, especially his friends. Ino is his friend, so he has to save her from Sasuke.
The fanfiction 'naruto saves ino from bullies' might start with a scene where Ino is alone and the bullies surround her. Naruto, being the hero, senses the trouble. He dashes towards the scene. He might start by taunting the bullies to draw their attention away from Ino. Then, he could use his speed and agility, which he has developed through his training with Kakashi and others. Once he has the upper hand, he'd make sure the bullies know not to mess with Ino again. After that, he and Ino would probably have a moment of relief and gratitude, strengthening their friendship in the process.
In many Naruto fanfictions, Naruto might save Sakura from bullies by using his ninja skills. He could use his shadow clone jutsu to surround the bullies and intimidate them. Maybe he'd also give them a stern talk about kindness, as Naruto has a big heart.
Well, perhaps Naruto has been observing Ino for a while and when he finally sees the school bullies picking on her, he steps in without hesitation. He might use his Uzumaki charm to first try and talk the bullies down. But if that doesn't work, he'd be ready to fight. His Rasengan might not be necessary but his basic ninja skills would be enough to send those bullies running. And this event could be the start of a closer friendship between Naruto and Ino.
A plot twist might be that the bullies turn out to be working for someone who wants to test Naruto's resolve. So, after saving Ino, Naruto discovers this and has to be on guard against further attacks. Also, it could be that Ino was faking being in trouble to test Naruto's friendship, but then real bullies show up and Naruto still has to save her for real. This would add an interesting layer to their relationship.
It could be Orochimaru. He might be interested in Ino's unique abilities, like her mind - control jutsu, for his own evil experiments. So he kidnaps her, and Naruto has to fight against Orochimaru's snake - like techniques to save Ino.