Looking at the picture and reading between the lines, where it doesn't mention integrated or hidden headset, I'd say it's a conventional 1-1/8" pressed in headset. Threaded or threadless depends on the fork, and stem used. Either way, these are highly standardized and all the same dimensions, so feel free to buy the headset of your choice.
You'll need a few tools to press on the fork crown, and frame cups.
Enjoy the new wheels when you're done.
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