Forest, fins and feet
Giant Mushrooms, the first forests, 28 foot long armored fish hunting sharks who were hunting smaller fish. In shallow streams and ponds, some fish were changing, becoming better at breathing air. They developed fins that could support their weight out of the water, if only for a little while at a time. By the end of the Devonian period, the fish that would become us crawled out of the water and went for a walk.
Here’s an article about the giant mushroom fossils.
Here’s an article about a shark who lived during the Devonian.
Here’s a larger fish that likely hunted the shark.
Here’s a couple of articles about the earliest known live birth.
Here are several videos that together, cover boney fish, the lobed finned fish, and how those fish developed into animals that walked on land, rather than living their lives in the water.