If you are watching the episode on a PC, you can use the to play the file and simply drag and drop the downloaded .srt subtitle file into the video window.
For Serbian (SR) or similar Ex-Yu languages like Croatian or Bosnian, the following sites are the most reliable: American Horror Story subtitles Serbian S08E07
: A large international database that frequently carries high-quality Balkan translations. If you are watching the episode on a