It's a level up, don't get me wrong, but if you can do the thing on the left (crochet a granny square), you can probably figure out the thing on the right (interlocking or double filet crochet).
Then you would have this:
Here is the entire pattern: (Download the PDF here)
Every row is illustrated, and it uses a simplified form of notation that's meant to be more like closed captions on a video than anything. It's different, and difference is scary, but you'll be fine.
There are no mid-row colour changes, no cut or carried thread, no bobbins, and exactly four ends to weave in. The PDF includes documentation, border instructions, etc., and there's also a video on that page that I hope to re-record but which should be enough to get you started.













