Because this is a "WEBRip," you need a subtitle timed for a 23.976 fps (frame per second) source. Most subtitles tagged for "WEBRip" or "WEB-DL" will work across different groups (like SHITBOX, EVO, or RARBG) because they use the same digital source. Search these reputable databases:
If you only want subtitles for the foreign/fictional language parts, look for a file labeled "Forced." subtitle Dune.2021.1080p.WEBRip.DD5.1.x264-SHITBOX
To delay the subtitle (if the text appears before the actor speaks). Because this is a "WEBRip," you need a