I think that you read a book at home and then add it .Basically for example,you have read Harry potter and the prisoner of azkaban at home.Then, you search it ,rate it and write a comment and press the pink"add to title " (or something like that anyway)and it’ll mark that book as read !

I hope that helps.

This is not for reading – just for reviewing and keeping track of your challenge.

I recommend Enid Blyton