Where can I find a comprehensive programming guid for ESP32, I know it's basically C but I need to know the details of e.g. how to set a GPIO pin low. I can see from the auto=complete in ESP-IDF that the syntax is different from other IDEs like STM32 Cube IDE. STM have programming guides for all the...

When I run the ESP-IDF 5.2 PowerShell shortcut it all works but there is a warning message "Setting PYTHONNOUSERSITE, was not set". Is it important and how can I fix whatever is causing the message?
Thanks
Steve