For that display you need to use three 7447 chips one for each digit along with the current limiting resistor for each segment.
Each 7447 chip then needs four outputs from the Arduino connected to it, so a total of 12 outputs. Each group of four outputs determine the digit that is shown on that display.
To help you with your software you need to use arrays, as shown here:- Arrays
An example of multiplexing is shown here:-
Of course you don't need the fourth display but the circuit is the same. All the same segments on each display need to be connected together.