Someone wanted to learn this too, so Grasp built them a personal learning path.
You can keep exploring this one or create a path like this one shaped around you.
Recommended resources
Module 2
Analog Components and Signal Conditioning
Module 3
C Programming Foundations for Embedded Systems
Module 4
Microcontroller Architecture and Digital I/O
Module 5
Analog Interfacing, Timers, and Interrupts
Module 6
Serial Communication Protocols
Module 7
Power Management and Battery Systems
Module 8
Professional Embedded Development with STM32
Module 9
PCB Design and Fabrication with KiCad
Module 10
IoT Systems: Wireless and Cloud Integration
Module 11
System Integration with Raspberry Pi
Module 12