Install Arduino Mbed OS RP2040 Boards on Arduino IDE, to program Raspberry Pi Pico in Arduino framework.

With ArduinoCore-mbed Release 2.0.0, Arduino now support Raspberry Pi Pico officially. To program Raspberry Pi Pico in Arduino framework, install Arduino Mbed OS RP2040 Boards in Arduino IDE's Library Manager.

The video show the steps:

Next:
~ RPi Pico (Arduino framework) + 128x160 ST7735 SPI TFT, using TFT_eSPI library