There are only 3 components to this project. Total cost about $50.
1. 3v buzzer CMI-1295IC-0385T — digikey $1
2. SCD 41 — Digikey $42
3. TTGO T-Display ESP32 CP2104 WiFi bluetooth Module 1.14 Inch LCD Development Board $11
The SCD41 also comes as a development board from a variety of sources—some have STEMMA QT connectors for easy hookup. These boards would make the whole unit considerably bigger but the all the rest of the components would be the same.