Kamen Rider Teacher from Blue Files

When he came back to his senses, Nan Zhixing found that he was already sitting on a starting train. The train was traveling at high speed. The scenery outside the window kept receding, but he knew nothing about the rest of the journey.
Why am I on the train? ?
Where does this train depart from? ?
Where am I going? ?
Nan Zhixing had three questions in his mind, and then tried to recall it, but as soon as he had the thought, his head felt a twinge of pain, followed by a flood of memories.
He, Nan Zhixing, a new century boy who once grew up under the red flag, inexplicably traveled through time on the day he received the college admission notice.
Physical and mental time travel, but in the world of Kamen Rider series.
That's right, the series world.
Whenever Nan Zhixing completes an unknown goal, he will go to the next knight world, just like clearing a game, until he has cleared all the knight worlds.
Time flies, since he first entered the world of knights, Nan Zhixing is now 23 years old.
Next, he will take this train to a strange city called "Kivotos" to become a school teacher.
and many more!
Why did I go to Quivotos to become a teacher?What kind of strange city name is Kivotos? It sounds... a little familiar?
Nan Zhixing lowered his head and continued to recall, but found that he could not remember anything about these three questions.
Normally, his memory is not bad enough to forget these things, but now, no matter how concerned he is, he still has no clue.
Isn't this another knight world, and I have actually been brainwashed and transformed by the villain organization?
Nan Zhixing raised his head and wanted to look at the window opposite to see if his appearance had been changed, but unexpectedly saw a line of slightly abrupt blue characters.
"The system has been successfully activated and is starting up..."