Hi,
First you need to decide your requirements (we can't help on this, it depends on your application and your ideas)
Then you need to read the ADC setup on the available options and how to set them
Then you need to write the according code
We won't read the datasheet for you, nor will we write code for you.
So give the requirements, show your code, give additional informations...
like
* error messages
* what does not work like expected ... with the information what you expected and how you tested this
* schematic, timing informations...
Then we will be here to help to rectify mistakes.
Klaus