I'm sorry, I haven't actually watched 'Yaariyan 2' so I can't give you the full story. But generally, it might be about relationships, friendship, love and the journey of the characters. You could try to find more details on movie review websites or by watching the movie itself.
Since I'm not completely sure about the specific 'Yaariyan' story, but if it's the movie, there are young characters who are friends. They each have their own distinct personalities.
Ye Feng was a character in the animated series " Battle King: Hurricane Battle Soul ", he was also one of the four main characters in this series. He was an optimistic, cheerful, and strong-willed youth. He had the Wind Spirit, Gale Wings, and the Righteous War God's War God Top Explosive Giant Fist. In the story, Ye Feng had participated in the Gyroscope Competition and defeated God of War with other characters, protecting Earth. He had the power of the God of War's elves in his body. When he used the power of the elves, his eyes would turn golden. Ye Feng established a deep friendship with the other characters in the movie and reconciled with the World War God during the journey. He was a straightforward, upright, righteous, and extraordinary young man.
Well, 'Yaariyan' might be something that I'm not super familiar with in great detail. However, typically a story with this name could be about the strong bond of 'yaariyan' which means friendships in Hindi. It might show how friends support each other through thick and thin, maybe in a college setting or in a small town where they grow up together, sharing secrets, having fun, and also facing some tough times like family issues or rivalries.
I haven't heard the full story of 'kaisi teri khudgarzi'. It could be a story related to a person's self - centeredness or self - indulgence perhaps. But without more context, it's hard to say exactly.