There’s already a tutorial for using the ESP8266 as a serial WiFi module. Note the ESP operates on 3.3 Volts, so connecting this module to the 5V pin means you’ll be out $5 and several weeks ...

We’ve seen a lot of ESP8266 projects in ... It also will lose frames on some WiFi events, but this is all forgivable when you consider this very inexpensive module isn’t meant to do video ...