If the publisher permissions of an eBook allow you to download a chapter or the whole book, then you should be able to transfer the downloaded file to an eReader that supports Adobe eBook DRM (Digital rights management) or reads PDFs.
However, some publisher permissions for eBooks only allow "read online" access only and these titles cannot be transferred to an eReader.
For more specific advice relating to the different eBook platforms, see the help pages of that publisher.