Please recommend a novel about rebirth.

The female protagonist returned to primary school after her rebirth and participated in the Mathematical Olympiad competition. Before the competition began, she met the celebrity she liked before her rebirth (also known as the male protagonist). That celebrity wasn't very popular, but his eyes were very beautiful. Later, they went to a university to practice questions related to the Mathematical Olympiad competition. There was also a male supporting character (I think his surname was Tang, I'm not sure). The male supporting character was the male protagonist's good brother. The female protagonist saw that their relationship was so good, so she wrote a book called Bright Moon and Breeze.(Or the Wind and the Moon, it was a romantic novel, where the female protagonist became a vicious female supporting character and always broke them up). Later, the female protagonist wrote many novels. When practicing questions about the Orsay, she and the male protagonist went to foreign language classes every day (forgot what language, and the male supporting character also forgot where to go). There was once when the professor asked a question, only the female protagonist could answer it. Other college students could not. When the female protagonist was on the train, she met a woman with a birthmark on her face. She remembered a piece of news she had read before her rebirth. This woman was one of the important members of a large-scale child trafficking organization. The female protagonist immediately told the teacher sitting next to her that there was something wrong with that woman. She seemed to be a human trafficker. The teacher was convinced by her and called the police. A long time ago, I read a very good novel. I wanted to read it again, but I forgot what it was called. I couldn't find it even after searching for a long time.