Searching for with Greek subtitles (Υπότιτλοι Ελληνικά) typically refers to one of two cult-classic productions: the 1978 neo-noir film starring Ryan O'Neal or the 2014 BBC crime drama miniseries. The Driver (1978)
This is a three-part British crime drama starring David Morrissey as Vince McKee, an ordinary taxi driver who gets involved with a criminal gang.
Look for ".srt" files on reputable subtitle repositories like OpenSubtitles or Podnapisi by searching for the title + "Greek".
If you already have the video file and need to add subtitles: