In modern versions of Windows 10 (1809+), RSAT is included as a "Feature on Demand." You do not need to download a separate installer.
ADUC is not installed by default on Windows 10. It is part of the suite. aduc windows 10
While ADUC is native to Windows Server, administrators managing domains from Windows 10 workstations must install it manually via Remote Server Administration Tools (RSAT). This guide covers the installation process, key features, and common tasks for using ADUC on Windows 10. In modern versions of Windows 10 (1809+), RSAT