
This is solo leveling ( ̄へ ̄)

Well, the boss is different. Just "an op boss" doesn't count as plagiarism. But everything else pretty much is. A weakling at the bottom of the party? Check. Encounters an op boss which wipes out everyone else? Check. Gets something that will allow them to level and become stronger than anyone else? Check. And per the title, doing it all solo? Check. Even the word on the cover page is "solo". And it looks like he'll be using a dagger or maybe daggers as well.
All that's missing is a girl that supports him from when he's still weak. Though I have no doubt he'll attract one or most likely multiple ladies soon enough.

I don't understand after read Spanish raws please someone explain to me ╥﹏╥

Basically the omega gets his heat while being at school, he hides away and the two semes find him and have sex with him, but everyone in the school has already noticed his feromones and they figure out that he is an omega, so they expell him from the school. But the alphas reveal that he was undercover in the school because of them, they found out he was an omega years ago but kept it secret from everyone, the school and Yuuze included. After that Yuuze feels really betrayed and kicks them out of his place. The alphas are really sad about the whole situation and that's why they are holding hands in chapter 7. It is implied that the reason Yuuze left his place is because of this whole situation. What the brother tells them is that he put a gps on the lucky charm he gave Yuuze back in chapter 2, so he knows where he has gone and is worried about it but his butler won't let him go there so he asks the two alphas to go find is brother instead (also turns out that Yuuze's brother is a brothercon).
I hope this answer your questions.
My big condolences for your adorable friend, and thank you for the update...be strong