If the learn guide and code was written to run on a specific board, the code could be using pin numbers or names that don’t exist on your board.
A good example of this is when a CircuitPython guide uses a Feather board as an example. The Unexpected Maker Feather boards follow the Feather format guidelines, but often the IO numbers selected for each pin will be different to the ones on the Adafruit (or other brand) boards.
In cases like this, you just need to look at where the wire is being connected, and refer to the pinout card or the silk screen on your board to identify the correct IO number and update the code to use that.
Why use different IO numbers to other branded boards?
Not every microcontroller has the same IO numbering system, and some don’t even have the same numbers at all. Even within the ESP32 range of MCUs, the original ESP32 has different IO numbering than the ESP32-S2 and ESP32-S3.
So often it’s just not possible to to make all boards that share a format (like the Feather format) have the same numbering on each pin.