Using File -> Save As -> PDF requires several skills
Window management in Windows GUI:
1. Usage of File Menu and/or Ribbon Menu
2. Knowledge of Word's PDF integration
File System knowledge:
1. What a "file" is
2. What "file formats" are
3. What a PDF is
4. That a word document can be saved or printed as a PDF
Etc etc etc
I work with non-technical folks all the time and printing/saving as PDF comes up often.
Usually in most cases I can install a PDF printer and let them "print to PDF" and they can understand it, but before they know the process, they look at me like I'm speaking Latin when I try to describe what files are, what PDFs are, what conversion is, what the file menu is used for, etc.