QMK Firmware Tutorial - MSYS2, and Drivers (Part 1)
By the end of this tutorial, you'll have a fully functioning MSYS2 build environment for QMK firmware on your Windows PC. The web-based configurators for QMK are great, but if you want to take advantage of all the features, fully customize your keymap, or just learn more about the way QMK works, you can get to editing the files directly. You'll need to setup a build environment first, but it's really not that hard. I'm not an expert in using MSYS2, Git, or QMK, but this process worked for me and first-timers should have no trouble.
I didn't detail checking out the firmware via Git since I thought dealing with .zip files was something beginners would be more familiar with. I'll talk about using Git from the command line in a later episode.
https://docs.qmk.fm/
www.msys2.org
https://github.com/qmk/qmk_firmware
https://kbfirmware.com/ - This an unofficial online configuration tool that makes it really simple to get a .hex which you can flash to your keyboard. Doing it the way I've explained will make sure you're building off an up to date version of QMK, though.