I got introduced to camilla by following the doll sarah route and agreeing to turn her into a doll after that Camillia is introduced outside the enchantment shop. After meeting with her I proceed to go to Julia where Julia days that a power greater than Teacher is required to defeat Camillia so I got the mysterious book but as there was only 2 conversations with Camilla 1 outside the enchantment shop and 2 in my room but never got the option to pass the book. So can anyone tell me the exact steps and requirements to enslave Camilla 

You’re correct in using the Book, but you cannot give it directly to her. Go enslave Angie and keep her personality as normal, tell her about your plans to enslave Camilla, give her the book, and you should cone back hone to an enslaved Mayor