If I delete a sketchy download, is it completely gone?

I have a MacBook Pro 13" from 2012, running OS X El Capitan 10.11.

Earlier today I wanted to experiment with editing video and thought I'd test it on something I already had (just for fun), so I downloaded some software from this site: https://www.macxdvd.com/mac-dvd-video-converter-how-to/import-dvd-to-imovie-free .htm

As soon as I downloaded it, the green light next to my webcam (iSight) flicked on then off. It was just for a second but I'm paranoid that the software was trying to access my webcam. I deleted the file and emptied the trash, but how do I know if it's completely gone? Can it still access my webcam after I've deleted it?