Import project when only URL is available?

My son created a project for school a few years ago, using Adobe Express. I'd call it an animated presentation. I'd like to bring it into my account or convert it to a video or whatever might be possible so I can save it for posterity. All I have is the URL, and I can't figure out what to do from there. He's not at the same school, so I don't think he would still have access to the account in which he created it.