Building a standalone temperature-logging station with ESP32 that saves CSV readings to a microSD card with NTP timestamps and deep sleep.
Controlling a relay via a web server on ESP32, with a very important safety note on the hazards of working with AC voltage.
Wiring the FPM10A fingerprint sensor via serial UART, and explaining the enrollment and matching stages for storing up to 127 fingerprints.
Connect a 1.8-inch ST7735 TFT over SPI, with correct 3.3 V logic guidance, breakout-board checks, library selection, and display testing.