Microsoft will release Windows 10 2004 Edition, aka Windows 10 May 2020 Update, to the public tomorrow, and the new major Windows 10 update is not officially available to the public yet.
However, you can now download the Media Creation Tool for Windows 10 2004 from this link below, install the tool and then follow the required steps to already install the Windows 10 2004 update.
https://software-download.microsoft.com/download/pr/MediaCreationTool2004.exe
The Media Creation Tool for Windows 10 2004 is not yet available on Microsoft's MCT page, so the tool cannot be downloaded from the official MCT download page.
The Windows 10 May update includes a lot of new features, including Windows Subsystem 2 (WSL2), the new Cortana app, Notepad improvements and more.
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