Define the Variable (where you want to put it)
#define BK_LIGHT_SETNG 0x00
write to the location
eeprom_write_byte((uint8_t*)BK_LIGHT_SETNG,0x7); //! read the settings
Reading the byte
xx = eeprom_read_byte((uint8_t*)BK_LIGHT_SETNG);
you don't need to do anything from scratch, The work has already been done for you just use the interface header files.
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