Coiling Dragon (Pan Long) - Vol 6 Chapter 11: The Man Behind the Curtain

Jiang Pengji got something called the Court Intrigue Stream System.
System: “Your goal is to become the most prestigious woman in the kingdom (the Queen)!”
Jiang Pengji: “Okay, System. No problem!”
Years later, she met the target by becoming the most prestigious woman (the Empress).
Jiang Pengji: “Well done, no?”

- Description from Novelupdates

Cho Ryu Hyang was good at math from a young age. When he enrolled into the The Theoretical Maths and Martial Arts School, the teacher, Jo Gi Chun, recognized Cho Ryu Hyang’s talent immediately and took him in.

Imperial soldier Suldak Helansa joined the infantry regiment of the Grand Duke Newman in Bena province, participated in the Warsaw plane war, and rescued a young man in the forest battle. This qualified young man suffered some injuries. Injured, still a mute, Suldak brought him into the barracks, and what we are telling is the story of this young man of unknown origin…

- Description from novelbuddy

Yuki, a high school junior, dies heroically saving a stranger and is reincarnated in a fantasy world, where he discovers an extraordinary and unrivaled power.