Don't trust academics with art. I'm not going to say art is subjective, it's got a lot of rules and structure to it a lot of people ignore. If you want to get better the best you can do is learn the fundamentals. Nobody's a genius with art and the 'big names' that crop up are usually just experienced and landed a lucky job as a concept artist or appealed to some rich guy's fetishes.
Taste however is subjective. Learn what you like to see and like to make.
But to be actually useful and give some starting advice:
Always use references and draw with your eyes and not your brain
Learn perspectives (A strong perspective takes a boring scene and makes it cool, imagine all those promo images of a person extending their hand towards the camera for example)
Play with tools but don't get expensive stuff. Pencils are good for learning and sketching, pens for strong lines, colors are something you just gotta learn how to use.
Color theory. Learn it.
Don't have shame in looking for help but don't ask general people their opinions on your art. Ask people who do art for critique, they'll give actual advice.
Learn how to do proportions. The standard is the 6 head model.
Once you learn how anatomy works you can play with it (This is incredibly fun)
Composition is important for most things. There's a few ways to do it, the Golden Spiral is one of the tried and true for a reason but grids also work well.
Learn what you want to make. Do you want to make anime, your own cartoon style, realistic, a blend, maybe you want to work with paint or with markers, hell you might like making pixel art or tiny but detailed images with pen. Experiment as you learn, never know what might click.
If characters is your jam look into character design.
And of course use tutorials and study existing art you like. Pick it apart bit by bit until you understand it and try to work from it.