These are cheap development boards with a STM32F030F4P6 MCU which contains 16KB flash and 4KB ram.

These boards are quite wide and it's wise to attach the headers below only if two breadboards can be utilised side by side (see picture).

These boards can be programmed using SWD or with the STM serial boot loader in ROM. Both types of programmer are inexpensive but the latter more versatile if somewhat slower in operation.

          USB
RESET     POWER
SWITCH    LED

BOOT0                                   5V
PF0       GND BOOT0 3V3                 5V
PF1                                   PA14
NRST                                  PA13
VDDA                                  PA10
PA0                                    PA9
PA1                                    PB1
PA2                                    PA7
PA3                                    PA6
PA4----------LED                       PA5
GND                                    3V3
GND  GND CLK DIO 3V3  RXD TXD GND 3V3  3V3

Power is supplied on the USB socket which feeds a 3V3 LDO regulator. The USB socket does not support I/O, it's only for powering the device.