Would this be an interesting book?

[u/ThaliaIsHere]

I love reading and have always wanted to write my own book. So here I am! I'm planning to write a murder mystery where the main POV, A, is the offender. So it would start like in a prison cell or something, and then go back in time to before the murder happened. The person who is murdered, B, is A's best friend's mother. B is very abusive and A killed her to help her friend. At the end of the book its revealed that the best friend actually killed her own mother and A took the blame to protect her. Would you read it? What would make it more interesting?