use of spec sensor in arduino uno
In the specification sheet linked to in the post we find this:


  -30+/-10nA/ppm


This is a very small amount of current.  The Arduino ADC is a voltage sensing device and (unless modified) has a range of 0 to the operating voltage of the Arduino.  Usually 3.3V or 5V.

Converting nano Amps to that range of voltage will require additional hardware.  A stock Arduino and code are unlikely to make use of such a sensor.

The conversion of such small amounts of current to voltages measurable by a stock Arduino is not trivial. And most answers do not fit into the short format of stack exchange.  Here is an Engineering Design News article on the subject.