Click on any link to copy a file to where your computer is set to store downloads. If you are not sure where that is, you can find files by clicking a "Download" button in the Tools section of your browser, and change the download folder with Tools-View Dowloads-options in Explorer, with Tools-Options-General in Firefox, and with Customise (the Ξ button) - Settings - Advanced Settings in Chrome.
If a file opens in this window, you can save it from the window by moving your cursor to the file icon at the top left of the screen, or on the right lower side (depending on how your system handles pdf files). Then use the back button (←) at the top left of your browser to return to this page.