You can download Open Rails for free and find thousands of routes and trains on community hubs like TrainSim.com . 🛤️ Commercial Successors
Microsoft Train Simulator 2 (MSTS 2) is a "lost" title that was officially twice and was never released to the public. The History of the Cancelled Sequel
If you are looking for the experience MSTS 2 promised, the community recommends these modern options: ⚙️ Open Rails (The True Successor)