Arduino for STM32

so I saved the hello world example as a compiled binary.
I successfully uploaded the bin file with STM32Cube Programmer
and it runs fine.

I went back to Arduino IDE and now it uploads the code.

It seems the board is not reliably entering DFU mode. Sometimes I just need to power cycle it (unplug ...

So i followed this tutorial
https://www.sgbotic.com/index.php?dispatch=pages.view&page_id=49
STCube programmer is installed and can run.

My tools menu looks like this:
https://i.imgur.com/suTqBR0.png

I wrote the hello world sketch in the arduino ide,

/*
Blink onboard LED at 0.1 second interval ...

thank you for taking the time to answer. it helps.
I had looked at the GitHub I missed but the wiki. The wiki makes it easier.
Since I use Arduino I will keep to that-having no experience writing hex/bin.
Would there be any advantage using hex/bin?

so the black pill can be programmed over usb . What is DFU?

If the blue/black pill are programmed with ST-Link Mini V2 Programmer, what is the usb port for?