Kakashi’s teacher was the Fourth Hokage. At that time, Lin and Uchiha Obito were on the same team as Kakashi. Kakashi's Sharingan was Obito's gift to him before he died.
Naruto's father has been confirmed to be the Fourth Hokage, but his mother's life experience has not yet been clarified.
What’s interesting is that the fourth generation’s teacher was Jiraiya, Kakashi’s teacher was the fourth generation, and both Kakashi and Jiraiya were teachers to Naruto.
The master-disciple relationship is as follows
The third generation: Jiraiya (Jiraiya helps Naruto train), Orochimaru (dsw helps Sasuke), Tsunade (the fifth generation helps Sakura).
Jiraiya: The fourth generation, Payne (Zero, the second leader of the Akatsuki organization, Zero takes orders from Uchiha Madara), Konan (Payne's partner).
The fourth generation: Kakashi, Obito, Lin.
Kakashi: Sasuke, Naruto, Sakura.