The Arduino boards have EEPROM because it's built into AVR chips they use.
The Espruino boards don't have EEPROM built in - STM32 chips don't include any EEPROM.
There's a "fake EEPROM" module that uses the flash (flash that's not being used to store code, ofc) to give functionality that looks a lot like EEPROM:
Or you can connect an external EEPROM:
Very clear and detailed. Thanks. One small question. For the Arduino(Uno) they are distinguishing between Flash memory and EEPROM. Are they the same for the Espruino ?