A wonderful article about installing RSAT (Remove server administration tools) on Windows 11 is available at How To Install RSAT On Windows 11 PCs HTMD Blog (anoopcnair.com)
I would like reiterate something Anoop has mentioned in his article. If you are using Microsoft SCCM or Windows Update Services (WU), then you must enable the local group policy as he has mentioned clearly in his post.
The image attached by Anoop could be bit confusing for the local group policy setup, hence I am uploading one with better visibility. The path is “Computer Configuration->Administrative Templates->System” & you need to open “Specify settings for optional component installation and component repair”
No need to reboot the computer for installing RSAT components. Follow Anoop’s thread and be a happy Administrator!