Local Users and Groups is a Microsoft Management Console (MMC) snap-in that allows you to manage user accounts or groups on your computer1. If you cannot find it in the MMC console, you can add it manually by following these steps2:

Press Windows key + R to open the Run dialog box, or open the Command Prompt.

Type mmc and hit Enter. This will open a blank MMC console.

Click File and then Add/Remove Snap-in.

In the Add or Remove Snap-ins window, select Local Users and Groups from the Available snap-ins list, and click Add.

In the Select Computer window, choose Local computer or Another computer, depending on which computer you want to manage, and click Finish.

Click OK to close the Add or Remove Snap-ins window. You should now see Local Users and Groups in the MMC console.