I’m new to sketch up and am trying to import a background image. However when I click on the download option my computer doesn’t allow me to see or select any images. I’ve tried saving images at JPEG and .JPG and neither works. I’m using sktechuppro 2017
What download option are you referring to? If you want to create a background image, use File>Import . Select the file type and select Use as image. Then import the image.
When you installed SketchUp did you right click on the installer and choose Run as administrator from the Context menu?