While "free downloads" (pirated versions) of v2.0.22 exist, they come with significant downsides:
You are a lone engineer on an alien planet. You mine iron and copper by hand. Then you build a machine to mine it for you. Then you build a machine to build the machines. Then you build a train to move the resources. Then you realize your iron is low, so you expand, fight bugs, and optimize. The goal: build a rocket and escape. Factorio Free Download -v2.0.22 Space Age DLC-