You're not stupid, don't be hard on yourself
Well, from what I understand so far in the story, the first part is actually their past lives
In the first part, Kloff is an alpha, so is Aeroc. But Kloff is engaged to Rapiel (who is pregnant). Aeroc is interested in Kloff, but Kloff rejects his advances. So Aeroc orders some men to juts scare off Rapiel. The plan unfortunately goes wrong, and those men end up killing Rapiel and the unborn baby. As revenge, Kloff made sure to strip Aeroc of his title, he bought his estate which made him lord Teiwind. Then he repeatedly raped Aeroc. Since Aeroc was exposed to Kloff's pheromones, he became an omega and birthed Kloff's children (6, in total if I'm not wrong). I think Aeroc also tried committing suicide, but it failed and it angered Kloff because he thought that was too easy if Aeroc died that quick. So, to prevent that he made Aeroc live in a cabin on the estate, forbid him from having any contact with the kids, let him fend off for himself and live in a terrible environment while still taping him.
At the end, Aeroc died during his last child birth.
Now in this part, it seems to be their second lives. In this life, Aeroc remembers everything until his death. Kloff doesn't remember anything though.
At first, Aeroc tries to distance himself from Kloff in order to avoid making the same mistakes.
But things happen differently though. For instance, Rapiel's and Kloff's engagement ends. Aeroc still turns into an omega. And also this time around, Kloff consciously wants to be with Aeroc.
We also get some details we didn't have during their first lives (example - they were bonded, or Kloff was deeply moved by Aeroc's death even though he was resentful, or how we learn that the kids they had learned the truth about Aeroc and how Kloff treated him, and left him to live alone in the Teiwind estate).
Also, Kloff has dreams of their past lives but just sees them as dreams for now at least.
So...yeah, so far that's what I can tell you. I don't know if it helped.
Take care.
Honestly, I can't remember the specific chapter.
But if I recall correctly, I think it was a flashback. Kloff was old and Aeroc was already dead for a while now. I also don't remember the exact circumstances in which the kids learned the truth, but they ended up leaving the estate, leaving behind Kloff.

Help a girl out I've been reading this manhwa for some time now and I'm quite confused..who should I look out for, who is good who is bad..Whats happening between the main characters like genuinely..i don't know just please guys help me out so I can understand better in the future chapters..I know I'm abit stupid but come on..English isn't my 1st language and I dont know half of these words..IM SORRY GUYS