Electronics is learned with your hands. These five projects take you from blinking lights to a connected device: an Arduino traffic light with proper timing, an ESP32 weather station with a sensor and display, FreeRTOS multitasking, Bluetooth Low Energy control from your phone, and finally an MQTT dashboard with Node-RED.
Each one is a code-along video, so you can pause, wire it up yourself and adapt it to your own ideas. Pick the project that matches the module you've just finished and come back for the rest.
Build a traffic-light controller on an Arduino Uno using a simple state machine and the millis() timer, with no delay() calls, putting GPIO and timing into practice.
Wire a BME280 sensor and an OLED display to an ESP32 and show live temperature, humidity, and pressure readings, using the I2C protocol you met earlier.
Use FreeRTOS to run several tasks at once on the ESP32, such as blinking two LEDs at different intervals, as a first step into real multitasking firmware.
Use Bluetooth Low Energy on the ESP32 to send commands from your phone to control LEDs and to receive temperature readings back.
Build an environmental monitoring and control system with an ESP32, a DHT11 sensor, the MQTT protocol, and a Node-RED dashboard that shows your data live.