How to translate the book pages content using the Book Translation module? My requirement is that a user can see the complete book pages in the selected language (English, Hindi, Bengali, etc) as per the preference. That's why I installed the Book Translation i18n_book_navigation module. 

As I installed the module and enabled the language block but it didn't translate my node's content. It only translate the inbuilt of Drupal taxonomy like View, Edit, Outline, etc into other languages. Do I need to configure some other settings for translating the book pages content or am I missing any module to install or enable?
If I understood your question correctly, you need to enable translations for the "Book page" content type.


Go to /admin/structure/types and click on "Edit" next to the content type you use for storing the book pages.
Under "Publishing options" make sure that "Multilingual support" is set to "Enabled, with translation".
Save the content type.
After you save this, you can go back to the edit page and configure extended language options in "Multilingual settings" tab.