ffmpeg -ss 00:00:00 -i "Ghosts.S01E14.mp4" -to 00:20:00 -c copy "Ghosts.S01E14_Cut.mp4"
or more detailed:
To keep only the first 20 minutes:
It sounds like you’re looking for a related to the file/folder naming pattern: ghosts s01e14 ffmpeg ghosts s01e14 ffmpeg