You can read e-books online with your computer. This is generally done using a Web browser, especially for eBooks in HTML format. PDF formatted books can be read using Adobe software (which is usually installed as a plugin within your browser). You can also read e-books on devices such as the Kindle, iPad, or one of many kinds of smartphones.
You will typically see a page similar to below when you click into an e-book.
You will be able to browse the table of contents on the right, and then upon selecting a chapter or section, the pages will appear on the left.
Many e-books also allow you to search within the content of the book. In this example (which is from ebrary), the location of the searched term is indicated by a small green magnifying glass. Click that icon and you will be taken to that occurence of the term you searched.