CCS/LAUNCHXL-F28379D: the limit that the ADC can measure ?

Tool/software: Code Composer Studio

I'm using ADC to measure some values of voltages. But I have some questions :

- Can the ADC measure any value of voltage ? or is he limited to 3V ?

in the datasheet of ADC it' saying that : if ADCINy ≥ VREFHI then ADCRESULTx = 4095

- and is VREFHI equal to 3V ? (I'm using LAUNCHXL-F28379D)

hope someone can answer my questions.