The way to get start on art

what the purpose we learning for art? for my answer is just simple as i like to draw and i wan't to learn how to draw good art. after i join my first class for foundation in art my lecturer told me the interesting purpose about why we need to learn art. My lecturer told me that the purpose we learn art is for "visualize" something we are thinking in our mind. If we does't not have any basic skill or knowledge about art and we will not able to visualize what our mind thinking and what we wan't to express to people what we are thinking. Either you are using writing or body language you still not able to fully express the image that your mind thinking about, that why we need the skill and knowledge of art to express and visualize the image or object that we wan't to share with other.
The first lesson i learn in the class in what is the basic to start leaning on drawing. The answer my lecture give is we need to start learning by drawing a straight line for until we feel confidence to draw it by free hand without using ruler. The answer giving make me feel disappointed because what we learn is drawing a straight line for our first lesson. But after that i totally change my mind about that after the lecturer tell us the reasons to start learning from drawing a line because everything we learn is always come with the basic and drawing a straight line by free hand is the basic way to start learning for art. Never underestimate what a line can do on art because when we can form an art work by combine a lot of line either the line is straight or curve and the line also can be draw in different angle.For example after we learn to draw the straight line we can start drawing some shape like rectangle, cube, triangle or a polygon. When combine all this shape we can form a volume and than the volume will form an object. This all process one-by-one is how to draw a completed drawing for your art and it was very important for people who started to learn drawing.