How to interact via serial with a MCU (ros2 - Nucleo64)

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Hi all I am building a mobile platform. It is a classic three wheels differential driven robot. On the robot I have two BLDC motors controlled with simpleFOC arduino library, a Nucleo64 board programmed with arduino IDE 2 and a raspberry pi 4. I want to install ubuntu on the Rpi and use ROS2 on top of it. Humble if it is possible. I am not very sure on how to continue so i seek for some suggestions. Do you have any for me? Thanks in advance for your help!