How to convert a PDF file to an image
Converting a PDF to JPG using a mac computer. (scroll down for PC)
Click on the PDF and right-click and open with Preview.
Click export and a pop-up box will appear. Make sure the Format reads JPEG. If the resolution says 72dpi, change it so it reads 300dpi. The converted JPEG image will save on your computer.
Converting a PDF to JPG on a PC computer
Depending on what Microsoft version you have there are various add-ons that you can use to convert PDF to JPG. You can also try Adobe online, see below for details.
https://www.adobe.com/acrobat/online/pdf-to-jpg.html