You can add your full name to your Windows 10 local account — Here's how.

[Windows Central]

Do you want to display your full name on your local account? Here are three ways to do it on Windows 10.
On Windows 10, when setting up a device with a local account, you probably noticed that the Sign-in screen and desktop only display your account name, instead of your full name like when using a Microsoft account. The reason is that during the local account creation process, it's not very clear how to add this information nor there's an option in the Settings app to edit your account.

Full story from the WindowsCentral blog...