Hi there,
Unless I am mistaken, the words 'Ce livre' mean 'This book' in English. The example given uses 'A book'
Je lis un livre. Ce livre s'appelle "Orgueil et Préjugés". -> Je lis un livre qui s'appelle "Orgueil et Préjugés".
I'm reading a book. A book is called "Pride and Prejudice" -> I'm reading a book which/that is called "Pride and Prejudice".
Thanks,
Phoenix