Here's the link to the section you needed in the training portal: https://dovetailmktg.kartra.com/portal/mgsitlogin/post/195
If you want to do videos and actually be able to edit them, here's a short list of some of the more popular programs out there:
Camtasia (most expensive around$200, most capable for desktop)
Kinemaster ($40 for phones only, but really capable)
Wondershare Filmora (desktop, cheaper but not as capable as Camtasia)
Soapbox and Loom are browser based. You can only trim beginnings and endings with these. I use soapbox for all of these videos I make. They're both like $10 per month or so if you want the versions that can download videos. (I shoot most of my videos using Soapbox.)