Gave my bike to someone and found it like this.

https://preview.redd.it/aqhoy48ydgch1.jpg?width=1368&format=pjpg&auto=webp&s=0a0a8bffc6770f757f2d945fdbc2b4c6967df5be

He's my borther and he claims he didn't crash anything, but I think he stored it leaning and pressing on the derailleur which probabbly caused this.

and when I tried puching it back it's really hard and I don't want to break it.

What am I supposed to do? should I change the whole derailleur,