All you have to do is enter the url of a wiki page you want it to run on and tick the box next to:

add archives to all non-dead references (Optional)

You can also just enter the title of the page instead of the full url, i.e enter Grime_(music_genre) instead of https://en.wikipedia.org/wiki/Grime_(music_genre) - but either works!

Pages with a lot of sources can sometimes take some time to complete (it does it all in the background for you), this is normal :)