To create a PDF of your score, the approach is to first generate a print layout, then save that to a PDF file.
On Windows: Press print, and set your options. Choose the "Microsoft PDF Driver" as your printer form the drop down list. When you press print, you should find that a dialog box appears; choose where you'd like to save your PDF to.
On iPad: Tap share, then choose "Print / Create PDF". Set the options however you like, then tap the "Create PDF" button. The iOS share sheet will appear and allow you to save the PDF file, AirDrop it, Email it etc.