Hello RuijieZhang1,
My Name is Paul one of the Community Advisor and a Microsoft Consumer like you. I do apologize if you are having issues with your Windows 10 Machine and I am here to help you.
You want to remove via User Accounts and here's how to do it.
* Click START and search and open CONTROL PANEL.
* Click USER ACCOUNTS and Click MANAGE ANOTHER Account and try to delete the account that you wanted to be removed.