I am going to plug Andy Astbury's YouTube channel here, specifically his fantastic RawTherapee tutorials. Where Adobe, MS, and other big companies thrive is the amount of high quality training and tutorials for inferior software. RawTherapee is an amazing piece of software that is hard to use with limited learning resources (compared to Adobe or Capture One) but people like Andy are fixing some of that.
Edit: Forgot to add a link https://youtu.be/310rCQZe0NI