I need help finding a webtoon my friend read

i used gpt and everything, i cant seem to find it. so i'll translate her post, let me know if there are parts that doesn't make sense in the translation and i'll fix them

The main character was the daughter of the king, she had a male twin, their mother died when they were young, then their father married someone new, had a child with her, never cared about his other children, and the stepmother bullied them a lot. Their country was at war, they were massacring a country a lot, then they exchanged their princes to their kingdom to end the war, and their princes to that kingdom for a while so that they could be educated and peace could be made. The prince of that kingdom was being tortured badly because he was a loser here (still children) and the girl was helping this boy and they were even sentencing the little boy to whipping and the girl was coming and putting ointment on the boy's wounds (still children) They became close and became each other's only friends and they had a teacher who was good to them she was the only adult and then a few years go by and the boy betrays their country in revenge and sets the city and the palace on fire and that's the last she sees of him but before that, because of the boy, the only person who was good to the girl and the boy is publicly executed and she tries to catch up but as she arrives, her teacher is beheaded in front of her eyes then something was going on in between, the girl's brother came back right away and their relationship was VERY GOOD, he was the only one who loved the girl and he was the guardian, and then her stepmother assassinated her brother where they were staying, and assassins were sent to the place where he was staying (during this time 13- 14 years old) the girl found out about it and went to where her brother was staying with a sword and fought back to back with her brother to take down the assassins and a fire broke out and then something happened and the girl's brother died in front of her eyes and at that moment the girl immediately made a decision, she cut her hair, took her brother's arm and threw his body into the fire and went out pretending to be her brother. she made herself look dead and then there was a counselor named Merlin who realized that it was a girl and then they started to train her with another counselor so that she would act like a boy HA meanwhile the girl disguised herself as her brother and had her stepmother executed and the other brother exiled (she was bullying him and it was a bit of revenge) then something happened and this girl went to that boy's country (15- 16 years old) he met a prostitute and the prostitute realized that he was a girl and he and the prostitute became friends or partners or something. HA there was a child king who came to this country when he was little, he was obsessed with this girl, he had a snake crown, then he was causing a lot of trouble for them, anyway, this girl was encountering that betrayer again and said that he was dead, the child did not react, but we saw him crying on the balcony from a scene, then many episodes passed, they were trying to escape from the death game of that grown-up child king and the betrayer. There were voices in her head, her psychology was not good, and there were the girl's counselors, the man called Merlin who knew that she was a girl, he tied the girl up and knocked her out, and at that time he had the other brother of the girl brought to the kingdom, he brought his brother to the girl and forced the boy to fuck her while she was sleeping, but his brother said ok and did not touch the girl, I think I remember that, I don't remember anything else, and the betrayer boy was very obsessed with the other king girl.