Solved! how do i transfer my downloaded subtitles to the actual online movie?

Jun 25, 2018
I am stuck, downloaded a bunch of subs for Mi-5 Season Ten, but cant figure how to move them from wherever I have them to the movie site that shows this show?
Is downloading the only way?
Cant I get an .srt thingee going?
Very computer nonsavvy, so dont hesitate to instruct as if for a two year old :0)
Many thanks