There are multiple ways to make a video available to view on the internet. This topic covers a way that's pretty easy if you already use Google Drive (free for a 15GB of storage). Google Drive is a cloud storage service that lets you store your files online and also sync them or make them available from your mobile devices and Mac or Windows computers. If you make a video and store it on Google Drive, you can share it by generating a link to it that is useable by anyone you send it to.
These help topics discuss various ways you can create your video on different platforms.
From your computer, you can copy a file to your Google drive by going to https://drive.google.com and logging into your Google account. Google Drive is structured like a real drive: you can drop things in to the main directory or you can create folders to organize them. Navigate to the location where you want to store your video and then drag the file's icon from the Finder (on a Mac) or File Explorer (on Windows) into the Google Drive directory view in the browser. Drive will not present a preview for the video immediately. It does special processing on videos that allow them to be played in a web browser. But this process doesn't take very long for short videos.
To share the video on the internet, right-click it in the Google Drive window and choose the Get link command. A panel will appear that looks like this:
There may be a blue tip balloon as shown here that you can dismiss by clicking Got it. The file defaults to Restricted sharing, which means it would only be available to specific people you invite. For use in audition forms, you should click this to change it to Anyone with the link. Finally, you can click the Copy link button to copy a link you can paste into the audition form's Link to Audition Video field.