Clicking a PDF opens Adobe Reader instead of Adobe Acrobat in Windows 10

Go to Start button

Choose the "settings" icon (looks like a gear)

Go to the Apps item

Choose 'Default apps" on the left column

Scroll down to the link "choose default apps by file type" under the heading "Default apps"

Then you will need to scroll quite a bit to find the file type of .pdf then to the right of that you should see that Adobe Reader is the default.  Just click in the Adobe Reader Icon and a box will pop up to choose a different program to be default. Adobe Acrobat Pro should be in the list to choose from.