The link to your textbook will be included in your syllabus and/or in Canvas. Some courses are built so that the readings are embedded in individual modules. Check with your professor if you aren't sure.
If you are off-campus, you will have to log in to the library's proxy in order to access the book in ProQuest Ebook Central. Once you login and access the book, you will be able to download it to your device. You can log into ProQuest Ebook Central by using this link.