Since you have a specific iTunes WEBRip release, you need a ".srt" file that matches that "rip" to ensure the timing is correct. Look for the exact filename or "iTunes" tag on these reputable sites:
the name of your video file: Chaos.Walking.2021.WEBRip.iTunesChaos.mp4 (or .mkv). subtitle Chaos.Walking.2021.WEBRip.iTunesChaos....
: In VLC Media Player , right-click the video while it's playing, go to Subtitle > Add Subtitle File , and select your .srt. Since you have a specific iTunes WEBRip release,
Subdl : Highly recommended for finding specific release matches. right-click the video while it's playing
English Subtitles: Often has multiple versions for the same film.