I Became the Alchemy Master by Picking Up Trash - Chapter 16 - 15: Going to School

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

Just days before his final discharge, Sergeant Shin Young-joon, a military chef by profession, witnessed the doom of the world.An apocalypse, that came out of nowhere and ruined the world that he used to know.In the blink of an eye his battalion fell into shambles, all the communication lines, and radio frequencies were severed, and before him was a message stating:[Congratulations on your awakening!] [Occupation: Novice Chef Lv.1] If only he had a profession like a warrior or an assassin, he might have attempted to stand his ground alone.But what was given to him was clearly the supporting job of a chef.With the recent developments in progress, he didn’t have any choices, other than saying, “From now on, I’ll be the one to feed you all.”

In her previous life, she rose from a country girl to become a CEO, working diligently until she died of overwork at 38, only to find that she had been greatly betrayed by her useless husband, who even had a child outside their marriage.When she opened her eyes, she was back to being eighteen years old, facing grandparents who favored boys over girls, a father who was honest and kind but dared not resist his parents, her mother who loved them deeply but was easily bullied by others, and her brother who still loved her despite her coldness.In this life, she decided to take her family away from those greedy relatives, save her brother from a fate of disability, and stay away from her useless ex-husband.Unexpectedly, she saved an even more important person by the roadside.“Your husband is just a country bumpkin; he didn't even get into university. How could you live well with him?” her ex-husband said.One day, a Bentley stopped next to her. A driver got out and bowed to her, saying, “Madam, the Boss is waiting for you for dinner.”“I know that car! It belongs to a rich family!” someone exclaimed.“Did he just call her Madam?” another person asked....“Did you hear? He brought a country girl home?”“They say that girl is his wife. Isn't it funny?”“Madam has arrived!” said the steward.“OMG, it's the talented girl from the famous university!”“Dear lord! She is the legend of the A-shares!”“I'm just so shocked...”“Hey, guys, she is my wife,” he said.

Humanity has been gradually transported to the Abyss by a bored god to compete against other races and monsters.The problem is… humanity failed. In a last desperate push the strongest survivors chose a comrade to travel as far as possible back in time.