The software that came with the 60D is too old to work with an 80D's RAW files.

Simply go to the Canon website of your choice, download and install the latest version of Canon Digital Photo Pro. That will be able to handle the 80D's files. Canon Image Browser (or whatever they call it now), will also be able to display thumbnail previews of the 80D's RAW files.

Think of RAW as "unprocessed" images. They require specific software to view and work with them. And it needs to be up to date with the camera involved, to do so.

JPEGs, on the other hand, are images that have been processed into a widely universal file type, which can be viewed easily with many different software programs.

Note: If you're using a Windows based computer, you also can't see Canon RAW (CR2 and CR3) files in Windows browser. They will just appear as generic icons. If you would like to be able to see thumbnails of them there, too, go to https://www.fastpictureviewer.com/codecs/, download and install the codec you'll find there (costs $10). It can interpolate thumbnails and even enlarged views of virtually any RAW file, right in Windows. This is handy for organizing or searching for a particular file, but the images in Windows are not color calibrated so unprocessed RAW files will naturally appear rather flat and low contrast. They have to be post-processed for appearance.