Dude drawing is all about patience, a steady hand, a unique view of things, and a big imagination. Develop each of those skills individually and together to master drawing.
It it good advice, but in my opinion some people are born with some abilities, eg. talent for making good combination of colors or sense of space. Talent is a 10% of results, 90% is a hard work and learning all the time. Time changes everything. If someone told you “Yours work isn’t good enough” or something like this don’t worry, take a deep breath and think: “That was yesterday, today is a another day”.