But if you want one to play with right now, search for “ESP32 ESP-WROOM-32 Wemos D1 LOLIN32 WIFI+BT 2.4GHz Dual Mode Develope Board”. (sic on the “Develope”) ...

A large servo and an ESP32-S2 make up the guts of an analog CO2 sensor. Behind that adorable face is a DS3225 servo being driven by a Wemos S2 mini, both of which [Cyrill] happened to have handy.