How do artists create form through art?

Not sure if there is supposed to be a static answer for this, but many artists develop form through inspiration that they see. Many forms of art that we use in the modern age derive from other forms that have been around for centuries. Other artists use nature as a form of inspiration.

The process of artmaking begins with the question, “What should I create?” You, as an artist have to ask the same question: what do you want to create? Maybe you don’t know where to begin. Even if you have an idea you would like to explore, it is valuable to expand your horizons by considering some of the ideas that other artists have investigated.

This is called adduction