How do I change the name on the welcome screen?

To change the name displayed on the welcome screen in Windows 11, you need to rename the user account associated with the profile. Here are the steps to do that:

1. Open Settings: Click on the Start menu and select Settings.
2. Go to Accounts: In the Settings window, click on Accounts.
3. Your Info: Select Your info from the left sidebar.
4. Manage My Microsoft Account: If you're using a Microsoft account, you may need to click on Manage my Microsoft account and change the name there. If it's a local account, you can proceed to the next step.
5. Change Account Name: For a local account, you can find the option to change your account name directly in the Your info section.
6. Sign Out and Sign In: After changing the name, sign out and then sign back in to see the new name reflected on the welcome screen.

Make sure to restart the computer if the changes do not appear immediately.

If you setup the user account on that device using your own Microsoft account, then that is why your name is appearing on the login screen, you would need to go to the Settings App - Accounts - Other Users - Add Account, then create a new user account associated to your wife's Microsoft account, then log out of the current account and into the new account and finally delete the original account created on the PC.