Most of our ebook vendors allow you to download chapters for printing or reading off-line.
Books from Ebook Central, for example, can either be read online or downloaded to your device for a limited time (usually 21 days). Skillsoft, on the other hand, only allows you to print one page at a time. How you add books to your Kindle/iPad depends on which vendor is offering the ebook.
If you provide us with an example of a book you'd like to add to your device, we may be able to provide more specific guidance.