The answer to this question is indeed correct.  Kakashi Hatake, the copy ninja, knew that  Naruto was Minato  Namikaze, the former fourth Hokage’s son.

Kakashi was part of Minato’s team from a young age. Now, despite knowing that Minato was  Naruto’s father, he kept it a secret to try to protect Naruto from the enemies who had been in his search due to his status as the nine-tailed beast Jinchuriki.

Kakashi’s Connection to Minato and Naruto

Kakashi had a special connection with Minato. He was Minato’s student and learned many great jutsus from Minato. Kakashi Hatake is one of the most skilled and famous ninjas in the Hidden Leaf village.

He even became the copy ninja due to his unique talent for using different kinds of jutsus. Besides learning jutsus, Kakashi also adopted many life principles from Minato. And that’s the reason why Kakashi didn’t allow the secret of Naruto’s parentage out.

The Secret: Naruto is Minato’s Son

Protective Measures for Naruto

Minato and his wife Kushina sacrificed themselves to protect the village from the nine-tailed beast.

With no option left, they had to seal the Nine-Tailed Fox inside of Naruto, hoping to protect the village from the rampaging  Beast and that Naruto could use the nine-tailed beast’s power for good.

But besides the nine-tailed beast, there were other enemies of the village from whom protecting Naruto was essential. And that’s why Minato and Kushina keep Naruto’s parentage a secret.

Kakashi’s Role and Awareness

Despite knowing that Naruto’s parents are Minato and Kushina, Kakashi didn’t release this sensitive information to anyone, especially among the friends that surrounded Naruto, because to respect his master’s wish and understand the risks involved, he never disclosed this information to anybody.

Even when he used to meet Naruto, he would never disclose his own identity to Naruto to protect him from all the enemies.

The Impact of Kakashi’s Knowledge

Guidance and Training

Naruto was part of Team 7, led by Kakashi, and consisted of Naruto himself, Sasuke and Sakura. Kakashi’s role in this team was to harness the abilities of Naruto as well as the other team members. This would help Naruto understand how to use his powers and cope with his heritage’s burdens.

So Kakashi’s training may have seemed like a way of teaching Naruto how to overcome the challenges of hosting the nine-tailed beasts sealed within him.

Mentorship and Protection

Kakashi’s main job was to act as a protective figure alongside Naruto and often related to his affection for his mentor, Minato, who was his inspiration as Kakashi acquired most of the abilities Kakashi received from his mentor, Minato.

Kakashi’s job was not only to provide mentorship to Naruto but to protect him from the nine-tailed beast’s dark energies and help him take valuable and responsible actions that would not affect his growth.

Conclusion

So, Kakashi Hatake knew that Naruto was Minato’s son and decided to keep it a secret to protect Naruto from the enemies who were searching for him because he was the Jinchuriki of the nine-tailed beast.