This is the standard official way to generate an ISO file on a Windows PC.
To download the directly from Microsoft, you can use the official Windows 10 Download Page . While Microsoft primarily promotes its "Media Creation Tool" for Windows users, you can obtain a direct ISO file by using a simple browser trick or by running the tool itself. Method 1: Using the Media Creation Tool (Standard) Windows 10 Pro Iso 64 Bit Download Microsoft
Select Installation MediaThe tool will ask what you want to do. Select "Create installation media (USB flash drive, DVD, or ISO file) for another PC" and click Next. This is the standard official way to generate