Please Answer, 1999

Something bad happened, what happened in 1999 was exposed. Zhou Hao, a senior high school student, was accidentally reborn into a world where spiritual energy was revived. He successfully passed the martial arts class with the help of a "quick practice cheat sheet". Who knew that this secret book actually contained key information to save all mankind. Not only did he sign a "confidentiality agreement", he also faced the risk of being punished by international law at any time. Oh my gosh, I was just a "kid" just coming of age.