Keypad&arduino

Hello and sorry for my bad english :smiley:
I'm working on a project with an arduino, a keypad (12) and PCF8574. I work in I2C.
I have realized my electrical shematic, but now i must do the soft .
It's the first time that i use arduino.
I need help, i can't use library " i2c_keypad.h "
Which library can i use for my programmation? Wire.h? Keypad.h?
An other question, i must do a methods for read the button tuch on the keypad, how can i say in arduino language: cols in output and read the line, after line in outpout and read the cols, and make a code for a touch on my keypad?
Thanks very much for your help ;D

What is your native language ?
There may be a forum section for that language which would help you considerably.