I was just wondering is there a difference on the the GPIO pins? I want to connect 8 pins of an ADC converter to my raspberry pi but now sure does it matter where i connect it.
GPIO stands for ¨general purpose input output¨
That said, you can connect the GPIO in a number of ways ´manually´ to read/write the adc|dac. Many adc|dac chips are designed for SPI, and you can connect the adc|dac to the standard SPI pins for use with the SPI library.
Read the spec sheet of the adc first. Study the SPI setup (if applicable) and then decide if you want to try to write your own (spi) or if you want to use the libraries. I will warn you, adc is tricky. And, further be warned that some adc chips have an eeprom that you can destroy by writing to the chip incorrectly; so make sure that you know what you´re doing.
Find examples on-line, and study what other people have already made work. Sometimes the adc makers will provide examples for you to study.