GitHub CI/CD automation for firmware development

Objective Set up a robust GitHub-based DevOps system to automate firmware development, testing, and deployment for Arduino, STM32 and Nordic controllers. How to since we’re starting from scratch, we need help to design the GitHub architecture and repository structure... (Budget: $30 - $250 USD, Jobs: Arduino, Bluetooth Low Energy (BLE), CI/CD, DevOps, Electronics, Embedded Systems, Firmware Development, GitHub, Microcontroller, STM32)