You will need the following to download titles to your Kindle Fire:
1. Internet connection
4. Adobe Digital Editions on your PC/Mac (see supported devices to check for compatibility)
Detailed instructions are available here from Ebrary.
Ebrary is compatible with any version of the Nook. You must first download the title to your computer and then transfer it to your Nook. Review these instructions for assistance authorizing your Adobe account on your Nook and transferring titles to your Nook.
Please note that not all titles are available for download. However, in some cases you are permitted to save PDFs of chapters or sections and transfer those to your Nook.