On Windows 10, installing version 21H2 (November 2021 Update) is recommended using the Windows Update settings, but you can also use the Media Creation Tool.
The Media Creation Tool is a standalone application that lets you download the files to create a USB flash drive media or ISO file to perform a clean install. Also, the same tool will enable you to complete an in-place upgrade without creating a separate bootable media.
You can download the Media Creation Tool from this Microsoft support website to download the Windows 10 21H2 files to perform a clean installation, an in-place upgrade, or to create an ISO file as soon as it becomes available in November.
The Media Creation tool includes an option to create a USB bootable media, which you can use to boot the computer to upgrade to Windows 10 21H2.
If the tool does not work on your computer, the Update Assistant is another application you can use only to perform an in-place upgrade.
Although this is a minor update that doesn’t introduce significant features or changes, Microsoft continues the gradual rollout of the new version to compatible devices.
Since April 15, 2022, the feature update has been fully available for devices that meet the requirements. If you need to download the Windows 10 21H2 ISO file directly, skip the Media Creation Tool using this workaround.