The Raspberry Pi Pico is a microcontroller development board built by the same makers of the Raspberry Pi. As seen in the Raspberry Pi Pico pinout diagram below, it has 40 GPIO pins with 3 analog inputs. It features the RP2040, a 32-bit dual ARM cortex M0+ microcontroller chip with a processing speed of 133 Mhz. The Raspberry Pi Pico is just one of many dev boards featuring the RP2040.
The Pico can run code either through CMAKE , Arduino IDE, or Python. Its pins are at a 3.3V level, just like most ARM-based microcontrollers.