Ok i gonna present you, one of my favorite manwha
Jo Pae, a not really sane boy, in our modern days, he wants to become emperor of Korea... His first step when he enters high school is to become the leader of the strongest school there is. No one expecting it, he actually takes down all of the school's yankees.
Jo Pae is now the enemy to kill! All rival schools wants his head whatever the means!
Action,Comedy, School life, Shounen
It's already completed in korea and have 12 vol, but english translators team started to work on it only now so ill say its ongoing, and they're at chap 18 atm. U can find it on almost all online reader site. I already read all of them in french few years ago.
Well if you like manwha of fighting and school life, u'll definitely like this one. At least give a try