How to get Windows 11 test previews from Windows Update
Open Settings.
Click on Update & Security.
Click on Windows Insider Program.
Click the Get started button.
Click the Link an account button.
Select Microsoft account Insider preview
Source: Windows Central
Select your Microsoft account from the list.
Click the Continue button.
Under the "Pick your Insider settings" section, select the Dev Channel option.
Windows 11 Dev Channel
Source: Windows Central
Click the Confirm button.
Click the Confirm button one more time to agree to the terms.
Windows terms for preview download
Source: Windows Central
Click the Restart now button.
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Open Settings.
Click on Update & Security.
Click on Windows Update.
Click the Check for updates button.
Windows 11 preview will download and install like any other preview you may have installed before.