I already change my user account in control panel but the
C:\Users\(user-name) is showing differently.
How do I change it to match my user account name?
You can do it - here is a handy how-to.
I probably would not take that approach however. I'd create a new account and transfer my data. I'd sync browser bookmarks, themes, add-ons etc. You can keep the old account until you are sure everything is working ok. Maybe not the quickest approach but works for me.