@colythdev the StickCPlus2 is a significant upgrade from the StickC, but easy to modify your code to suit.
https://github.com/m5stack/M5StickCPlus2/tree/master/examples
You can compare these M5StickCPlus2 basic sketches to the M5StickC.
Mostly, using this include helps:
#include "M5StickCPlus2.h"