Arduino Uno & Wemos (0.66” Across) OLED Shield
The first thing I see when googling "0.66 lolin oled" is the link to https://wiki.wemos.cc/products:d1_mini_shields:oled_shield and their Get started guide. This yields the libraries to be used with it:


for the OLED: https://github.com/mcauser/Adafruit_SSD1306/tree/esp8266-64x48 with the dedicated test sketch
for the A &amp; B buttons: https://github.com/wemos/LOLIN_OLED_I2C_Button_Library