Which is the best work from Goethe?
Assuming that literature is not an exact science and that works cannot be divided into objectively assessable works, such as good, bad or excellent, and that Goethe created a large number of pieces, I will answer the question as follows:
The most important works for Goethe are Goetz von Berlichingen and The Sorrows of Young Werther, since these works gave him initial fame in the Sturm und Drang period.