The original RTM build (10240) reached end of support years ago. It no longer receives security updates. Installing the pure RTM build today is a severe security risk unless you immediately update it to the latest version (22H2) via Windows Update.
Microsoft does not directly call it “Single Language” in the consumer tool, but the tool automatically detects your current license or lets you select the correct edition. windows 10 rtm core single language iso download
This article will serve as your complete, 2,500+ word resource. We will cover: The original RTM build (10240) reached end of