Here are images of galaxies from when the universe was only 900 million years old. The early universe was opaque from cooled gas, but around 1 billion years after the Big Bang it eventually became transparent like it is today.
The Webb telescope was able to resolve how the early opaque universe became transparent. The stars in these early galaxies were able to heat up the surrounding opaque gas and ionize it causing pockets of transparent gas. Over time this gas expanded and the entire universe became clear.