Note: this article was created on an older version of my website, so to save myself some time and work I'm just embedding it here for now.
If you'd rather read this article in full screen (especially if you're on mobile), click here.
I know AVR microcontrollers are somewhat outdated nowadays, because espressif chips are just on another level, but I was forced to use one for a class so perhaps this will be useful for someone in a similar boat.