Unity powers big hitters such as Hollow Knight, Escape from Tarkov, Cuphead and dozens more, and is particularly popular with small-scale indie developers. Even if you've never toyed with the idea of making a game, it's certainly worth having a nose around the tutorials on offer, at the very least to get a better understanding of the work that goes into game development. Like all professional game engines, though, Unity is pretty vast, so check out Getting Started with Unity first.