EndNote also allows you to download full text articles for your references. However, this function is limited by the library's subscription and other technical issues, so you might only be able to get 3-4 PDFs out of 10 references.
Be cautious! Do use this function with care and only download the full-text of the articles you intend to read. If you use this feature for a huge library, you might trigger off excessive or systematic download which is prohibited and may cause University-wide suspension to affected databases.
Steps Find Full Text
For the rest references, you still need to download PDFs separately and then attach to the references.
Steps Add PDF to references