The project book, written by well-known Elektor author Dogan Ibrahim, is an introduction to using the Raspberry Pi Pico Experimenting Kit. The kit is
Raspberry Pi Pico MIDI “pack” Interface – Simple DIY Electronic Music Projects
multiwingspan
Kitronik Discovery Kit for Raspberry Pi Pico (Pico Included) — Robotix Education Inc.
Raspberry Pi Pico
Getting Started with Raspberry Pi Pico
Introduction to Microcontrollers and the Pi Pico W, by Page against the machine
Overview, Getting Started with Raspberry Pi Pico and CircuitPython
Raspberry Pi Pico Experiment Kit Buy
Raspberry Pi Pico DIY Workshop
Extra Resources for the Kitronik Inventors Kit for Pico – Kitronik Ltd
Grove Starter Kit for Raspberry Pi Pico Botland - Robotic Shop
Leap Motion Controller 2 + Raspberry Pi 4 8GB Complete Bundle - RobotShop
PiicoDev Starter Kit for Raspberry Pi Pico
20 Raspberry Pi Pico Project Ideas! - Latest Open Tech From Seeed
SunFounder Starter Kit for Raspberry Pi Pico with 40 Projects Online Tutorials, MicroPython C Piper Make Code, One-Stop Learning Electronics and Programming for Raspberry Pi Arduino Beginners Experts : Electronics