If you want to download subtitles with VLC as BS Player which automatically search subtitles for movies on start of the movie, then you should use VLC’s extension VLSub 0.9.10. It works on Windows ,Linux and Mac OS X. I tested it on Kali Linux.
Download VLSub 0.9.10 from this LINK. and install it on your PC .
If you’re Linux user then copy vlsub.lua to ~/.local/share/vlc/lua/extensions
cp vlsub.lua ~/.local/share/vlc/lua/extensions/vlsub.lua
Restart your VLC media player and click on View -> VLsub 0.9.10
then click on Search by name , select subtitle and click Download selection