This will update all MP4 files in a directory with a date in the format "YYYY:MM:DD HH:MM:SS". It was taken from an answer to this question.
exiftool -FileCreateDate="2023:02:27 17:00:00" -FileModifyDate="2023:02:27 17:00:00" -Quicktime:CreateDate="2023:02:27 17:00:00" -api QuickTimeUTC *.MP4