Hi and welcome to the forum.
From the webpage you supplied, it pointed to an arduino project that you can use as a starting point :
However this relies on the fact that the arduino has analogue inputs, which the Pi doesn't have. You will need to hook up an
ADC chip to the pi, to convert the analogue voltage across the load resistor to a digital form.
So you have some homework to do........
Various male/female 40- and 26-way GPIO header for sale here ( IDEAL FOR YOUR PiZero ):