Where to start . . 

By reading the extended Getting started with Raspberry Pi Pico PDF file when you want to program it in C/C++. Or read the Get Started with MicroPython on Raspberry Pi Pico PDF file when you want to program in MicroPython.

I like to program in C/C++ so I started with the Getting started with Raspberry Pi Pico PDF file and after a hour the commandline build stuff was working on my linux laptop. I wanted to try the option to use a Raspberry PI as a  development environment to play around, so I used a spare Raspberry PI 3 for that.

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