transformer design for smps

I have a couple questions, one is about identifying smps topology and the 2nd is about the 3rd winding in an example I found. I need to design a smps that can take

Vin: 70V to 105V and output 5V at 1A

I've chosen to use the mic9130 https://www.electro-tech-online.com/custompdfs/2012/03/mic9130.pdf

On the front page of the datasheet there is a "Typical Application" schematic, which is not to far off from what I need to do, it's
Vin: 36V to 72V
Vout: 3.3V @ 4A

So, I think I'll copy that design, but now I have to design a transformer... from the reading I've done about this, looks like one of the first things I need to know is the topology of my smps. That's my question, can anyone tell me the topology of this smps example? Looks like an isolated synchronous buck converter... or maybe a forward converter? Also I don't see how the third winding is supplying the stead voltage to Vcc, according to the datasheet Vcc operates between 9V -18V (pg 3) confusingly on pg 8 it says Vcc is typically 8.5V....

much thanks!

Looks like an isolated synchronous buck converter

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I'd agree with that: but I'm no expert on SMPS.

according to the datasheet Vcc operates between 9V -18V (pg 3) confusingly on pg 8 it says Vcc is typically 8.5V...

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I'd ignore the 8.5V 'average' (whatever that means in the context). Some of the graphs even show 8V. Go with 9-18V. The Typical Application, which shows the bias winding as providing Vcc = 12V, is consistent with that range.

thanks i think you're right