ENFOLD HEALTH – fullscreen slider video pop up help

Hi, I’m working on my site linked separately

on the home page on the fullscreen slider at the top, there are two images which scroll, the first one has a pink button in the caption saying ‘watch video’ – at present, the link sends me to youtube where the video is hosted, however I’d like it to open a video lightbox without having to leave my site. I know it’s possible to have the video play as the slider scrolls through but as it’a a longer video but I’d like visitors to choose if they want to watch it rather than it play automatically because I think a 2 minute video playing all the time might get annoying.

Cheers :)