Kakashi could also be a common character. He is Iruka's colleague and they both play important roles in Naruto's life. In time travel scenarios, Kakashi might be involved in helping Iruka adjust to the time - shifted situation or they could work together on a mission that is affected by Iruka's time travel.
It also improves Naruto's skills a great deal. He becomes better at combat and using his ninja techniques. For example, his Rasengan might be more powerful or more easily controllable after Iruka's training. Moreover, Naruto's confidence grows under Iruka's guidance. He no longer doubts himself as much and is more willing to take on challenges.
Physically, Iruka takes care of Naruto's symptoms. If Naruto has a cough, Iruka might make him herbal tea to soothe his throat. If Naruto has a fever, he uses cold compresses to bring the temperature down. He monitors Naruto's condition closely and adjusts his care accordingly, making sure Naruto is on the road to recovery as quickly as possible.
At first, it might start with Iruka showing simple kindness to Naruto, like making sure he has enough to eat. As time goes on, Naruto starts to see Iruka as a father figure. He looks up to Iruka and wants to make him proud.
Iruka can be a great source of emotional support. He can listen to Naruto and his family's problems and offer advice based on his own experiences. For example, when Naruto is stressed about his Hokage duties, Iruka can remind him of how far he has come and that he can handle it. Also, Iruka can teach Naruto's kids things that Naruto might not have time for, like the history of the village in more detail.
Iruka's teaching is more traditional, focusing on the fundamentals and the proper way to do things. In contrast, Naruto would be more about inspiring the students through his own story. He might say things like 'I was just like you once, and look at me now!' His style would be more about motivation and showing that there are different paths to success in the ninja world. Iruka would be the one to correct the students' form and ensure they understand the basic principles, while Naruto would encourage them to break boundaries and think outside the box.