UNIGINE engine is a fully-featured 3D platform designed for creation of interactive virtual worlds with a photo-realistic quality. This powerful and extremely flexible solution is used for real-time simulation (transportation, military training, etc.), visualization (architecture, media installations, etc.) and game development.
Download from https://developer.unigine.com/en/downloads/unigine_community
install in the install : .NET Core 3.1 SDK (v3.1.201) – Windows x64 Installer
run the dotnet command in cmd to check the installation
launch and download UNIGINE SDK
click on docs https://developer.unigine.com/en/docs/2.13