Remove carbon reduce emissions message from Windows update?

You can't directly remove or disable specific messages like the "carbon reduce emissions" one from the Windows Update section. However, you can try to hide the update if it’s an optional feature or message, by going to Settings > Update & Security > Windows Update > View update history > Uninstall updates, and see if it’s listed there. If it’s a system-wide message, you might need to wait for an update that removes it or use a third-party tool to tweak notifications.