Diagram 2

What tablet is pictured with what appears to be running Windows with 2 USB cables plugged in below it?
Never seen anything like that. 

It’s an Ockel Sirius A Pro. https://www.ockelcomputers.com

Hi I'm a newbie in astrophotgraphy. I'm confused as how is this mount guiding without a guide port? 

Using an ST4 port, aka “Guide Port” isn’t the only way to guide.

The preferred method (more capable, more reliable) is to use Pulse Guiding.

ST4, or “guide port” guiding involves the camera sending picture to a computer, which figures the correction and sends instructions back to the camera, which in turn sends the instruction to the mount via guide port.

Pulse guiding involves the camera sending picture to a computer, which figures the correction and sends the instructions directly to the mount via it own connection with the mount (serial, wired, wireless, ASCOM)