Click on the book cover or the view chapters tile of the book you want to read. Select the chapter you would like to read. You can elect to read the chapter now by clicking on the open book icon on the right hand side of the screen.
If you are a teacher, you can add the chapter directly to a group library by clicking the 'Add to group' link. Alternately you can click on the 'Add to my library' link to add the chapter to your personal library.
If you are a student, you can add chapters to your personal library by using the 'Add to my library' link.