USB absolute mouse mode issue

Hey guys. I've been trying to implement absolute mouse mode as you can see in the tutorial below however I'm not able to find the HID.cpp file. The file has most likely been moved/renamed since the tutorial has been posted like 9 years ago. Would help me a lot if any1 could help me fix the issue. Thanks in advance and have a nice day.

edit :

I see no tutorial

my bad, updated the topic

Which Arduino board are you using ?

I saw that just yesterday...
Arduino15/packages/arduino/hardware/avr/1.8.3/libraries/HID/src