I have yet another question - how do I run the following on a batch of .raf files, not just the one?
exiftool -software="Digital Camera X-T4 Ver1.00" dscf3438.raf
My OS is Windows 10.
Thank you for putting up with this newbie!
Use the directory you want to process in the command. You can combine individual files and directories in the command and exiftool will process them all. For example, this will process all the files in the /path/to/RafFiles/ directory as well as dscf3438.raf in the current directory
exiftool -software="Digital Camera X-T4 Ver1.00" dscf3438.raf /path/to/RafFiles/
Add -r (-recurse) option (https://exiftool.org/exiftool_pod.html#r-.--recurse) to recurse into subdirectories.