Aug 18, · The best way would be to copy the URL link of the music video and go to a website that converts it to an MP3. YouTube Converter & Music Downloader - Convert Videos to. Download music for iMovie. In a perfect world, you’d be able to add any song you want to your video. But in reality, it’s usually not that straightforward. To adhere to copyright laws, all major video platforms — including YouTube, Facebook, Instagram, and Vimeo — enforce certain music slicelive.com: Logan Nickleson.