Keep both the video and the subtitle file in the same folder.

Download from OpenSubtitles which offers versions specifically tagged for "BluRay x265".

If you speak German but need help with specific terms, look for "Forced" subtitles. For non-German speakers, ensure you download the "Full" SRT file.

Undine.2020.GERMAN.1080p.BluRay.x265-VXT (and compatible VXT/RARBG encodes). Language: English (Full and SDH available). Reliable Sources:

In VLC Player, you can simply drag and drop the .srt file onto the video window while it is playing.

For the best results, rename the subtitle file to match your movie file exactly (e.g., Undine.2020.GERMAN.1080p.BluRay.x265-VXT.srt ).

Find synced English subtitles on Subscene for various BluRay releases.

Alternative SRT files are often available via Addic7ed for multi-language support.