In terms of total beginner stuff there is a lot out there on Youtube. Spirit of the law does lots of mechanics stuff, and has some beginner guide things which will help.

In terms of current content my opinion would be that T90 is probably the best for beginner content, but if you don't mind going back a ways Resonance22 had some excellent videos for beginners from a few years ago. He's since moved onto other things but does a good job of explaining the basics, which should serve as a stepping stone onto other casters and streamers who are still active once you're feeling comfortable. My favourites are T90, Nili, and Hera, but there is a shit load of content out there on twitch, Youtube, and other platforms.