Open the video in a player like VLC or MPC-HC , which will automatically detect and load the text.
If you are looking to download the actual subtitle file (.SRT or .ASS) for this specific version, you can find it on these common repositories: OpenSubtitles YTS Subtitles subtitle Winterskin.2018.BluRay.x264.AAC-RARBGW...
The film follows a gun-shot man named Billy, who takes shelter in a remote cabin with a reclusive woman named Agnes, only to realize she has a dark secret involving skinless creatures that roam the surrounding woods [1, 2]. Subtitle File Breakdown Open the video in a player like VLC