Did some digging..

Found a video explaining how to use a MIDI keyboards https://youtu.be/4revAw3lT4g but, one can just emulate MIDI notes on a pc keyboard https://www.youtube.com/watch?v=9dqPwNZh_9E..

It did not explain why one was prefered, but this page https://producersociety.com/why-beginners-need-midi-keyboard/ made it clear, it got to do with ease of workflow because you can keymap stuff on it, and to get a more human sound as it can detect how hard a button is pressed (+more)

There is a lot of free DAWs (digital audio workstations), so that's pretty nice https://youtu.be/W8MMuaRmRiE

I got my curiosity quenched at least, but I won't need this atm.