The first thing to note is that Gutenberg was not the first to come up with the printing press, since it existed in China before. In this old thread u/FreudianSlip summarises the early Chinese history of printing, and here you can read about the technical side of things as written by u/keylian. And in this thread u/svendskov discusses the popularity of woodblock printing in China, and in another comment u/sunagainstgold explains why Gutenberg invented his printing press and the literary culture of 15th century Europe. I hope you may get a full answer from one of our users soon!