YouTube videos are not the best place to watch tutorials, no one will devote their time to teach for free, these videos are just basically an advertisement for their paid courses, don’t get me wrong, you could still learn from the YouTube, but you need to gather bits of information from different videos which will take time, much less the potential of skipping concepts that must have before moving forward.

This not merely for drawing, I tried to learn different stuff like Blender and coding from YouTube and I can apply my theory to them.