MSPM0G3507-Q1: Decoupling of internal VREF

Part Number: MSPM0G3507-Q1

Hello,

We are trying to minimize the amount of noise we get when sampling the ADC using the internal reference. It appears that we can improve the noise by using the external decoupling capacitance to filter the internal reference voltage, per the comment in the datasheet as shown below


My question is what register configurations (if any) do i need to perform to select:
1) the internal reference; and ,

2) to ensure this external capacitor is properly used.

Thanks,

Mark