ArduinoCore-API VS ArduinoCore-avr

If you want to really learn it I'd recommend Bro Codes C guide, that'll make it easier to understand, his C++ guide is a bit longer but once you know C++ it's a matter of going to the Arduino references and looking for the function you need.

First, go to the Language Reference, which defines exactly what the commands do.

A great way to introduce yourself to the syntax of C/C++ and, more specifically the various functions and capabilities of the Arduino is to go through the documentation's Reference page on the company's website and read through each function and keyword. By the end of the page you'll have a solid overview of the capabilities of the platform and a certain amount of familiarity on how to use them.

You need a Serial.begin and a Serial.println to see something on the Serial monitor. Have a look at the documentation or some sample programs to see these statements. If you don't have Serial.print statements, nothing will display because you are not asking for anything to be displayed. As for the gibberish when you reset, it is possible these are remnants from an old program. Make sure the value supply to begin matches your serial monitor's baud rate setting (i.e. 9600 from your original post).

You might want to have a look at the documentation.

If you study the Arduino Language Reference, you'll find |=, <<, >>.

The arduino documentation is (or was back when i did a lot of work with arduinos) very thorough. Book mark the reference material https://www.arduino.cc/reference/en/ its very handy to have close at hand.

Arduino Reference - Arduino Reference what i usually scroll through to get me through any projects and i started off same place as you not knowing anything about coding and it got me through most of the projects i started. best to just keep making mistakes though and eventually the sketch will compile.

You can find what you need to start programming with Arduino on this page: https://www.arduino.cc/reference/en/

Gotta pick some project that matters to you and do it. Putting Python code into production with multi-person teams is outright maddening, but for the individual who wants to put their skills on wheels, Python is a great place to start.

Another fun thing to try is

https://www.arduino.cc/

I got started with that buying an Arduino and a breadboard and a handful of 74xx logic chips and I started writing Arduino programs that would generate inputs to the 74xx chips and verify the expected outputs and thus taught myself C coding for the Arduino and how to make circuits with discrete logic at the same time.

Check out existing implementations like Arduino: https://github.com/arduino/ArduinoCore-avr/blob/master/libraries/SPI/src/SPI.h

4. https://github.com/arduino/ArduinoCore-avr/blob/eabd762a1edcf076877b7bec28b7f99099141473/cores/arduino/main.cpp#L46

you can always just use an ide but i use this one on my old chrome book https://www.arduino.cc/

You'll also need the avr C library and the Arduino library, and possibly a Makefile or similar to corral the compilation process

Ya for $25 you either want 4-5 clones, or support the official Italian Arduino makers as thanks for making the entire ecosystem possible by buying one of their own boards from https://www.arduino.cc/

It depends what exactly is she into. For electronics you can check out arduino. They sell full kits with everything you need - some components like leds, breadboard so you can create circuits without soldering and a small 8bit computer to control everything with. AFAIK they also sell kits specifically for education starting with middle school.

They are in via Arduino. ;-)