As always I recommend downloading VLC Media Player https://www.videolan.org/vlc/ if you haven't already (it's free!) and then open the video with VLC. In the top menu bar click "Subtitles" then "Add subtitle track" then select the English subtitle file. Give it a few seconds and then the subtitles should start working.
Thank you so much Ashley. I've only found time to watch a couple of minutes without subs, so far, but I'm enjoying what I see. (What a little con artist she is, eh?)