Welcome to the forum @acornrun
[I’m posting a copy of the photo you’ve linked to because Pinterest is an utterly maddening and bizarre site, on which you can’t actually just see or zoom a photo, you can only do some weird image matching search… I just pulled the actual image URL from the page source.]
Anyway, my personal hatred of Pinterest aside, here is the photo:
And I think that knot is a single Bosun’s Whistle Lanyard Knot which is described in ABoK (#788)
How to tie it
Two great YouTube tutorials here
IGKT Solent Branch How to Tie a Sailor's Knife Lanyard Knot
Paracord Guild https://www.youtube.com/watch?v=l3W0DuWspf4
It’s also described in Des Pawson’s Knot Craft
The knot is often doubled, which makes it look a little like a Turk’s Head tied around the standing part of a rope.