Make sure the column in the center has NO checked boxes - if it does, just click once on the check to get rid of it
On that same page, look at the right column; click on the button in the bottom right called INSTALL NOW
Then, when prompted by "What do you want to do....", click on SAVE
When it is finished downloading, it will show a pop up saying it has finished downloading. Click on RUN in that pop-up box.
Wait for it to install; if you do not see it, find the icon at the bottom of your screen (a black box outlined in red with a white three-pointed symbol inside). Click on that icon if nothing is showing.
A box will appear that says Adobe Acrobat Reader DC installation complete.