You'll have to start by studying the respective data sheets to figure out how to program these controllers:
- how to write code that they can understand (there's bound to be lots of registers that have to be dealt with),
- how to get your code actually onto that controller.
Now if you want to program them with the Arduino IDE you're going to need to write a "core" for them. That will include hardware-specific implementation of a great number of Arduino-specific functions (for that you're going to need the knowledge you gained in 1) above).
The first data sheet you posted is a microcontroller all right (an old design, status "not recommended for new designs" - and unsurprisingly a quick Google search did not turn up an Arduino core for it), the second data sheet is an ADC (apparently of similar age).