STM32F103C8T6 Blue Pill Test.  Product Link: https://diycnc.ca/product/stm32-development-board-pill/

Here are tools I am using to test this very popular board:

• STM32CubeProgrammer.  Test the ST-Link and Connection
• STM32CubeMx. Must have - to configure each of pins and logic unless you prefer to use source scripts to do so directly
• STM32CubeIDE. Must have to debug and flash the board

FAQs:

1. How to quickly test the board? A: For testing, we have flashed a simple script onto the board: Blinks the LED light once every second when the board is powered on. 
2. Is the Micro-USB or USB-C port can do flash?  A: The port can only be used for communication based on our testing. An ST-LINK V2 is required for programming.
3. If there is built-in test code in the board, how to erase it?  A: We use STM32CubeProgrammer for this process: Erasing & Programming → Erase flash Memory → Full Chip Erase. If the device cannot connect, press and hold the RESET button for about 2 seconds, then click Connect, and release the button.