If you are looking to get started with the simulator, here are the official ways to access it:

While there are similar titles on mobile platforms, the official sequel is designed for PC; be cautious of "free download" links for mobile that may not be official releases. Narrative Concept: "The v1.00-30b Build"

You can try the game for free by downloading the PC Building Simulator 2 Demo on the Epic Games Store, which lets you play the first five levels of Career Mode.