How can I open DE1 demo programs on Quartus II?

Hi, I'm a student and beginner with FPGAs. I'm assigned to project a FM modulator and transmitter from Altera's DE1-SOC.

I did some research about it and thought it would be a good start if I first managed to input and output an audio file through the audio jacks on the board. As far as i understood, I need to configurate the WM8731 CODEC through I2C and I came across people talking about the demo program that comes with the DE1 (DE1_i2sound). Yet, I have no ideia where to find this example. Can anyone help me with this?

Also, if you have any better ideas of where else to start, it would be greatly appreciated.