It sounds like it's not using the welcome screen, which is fine. If you have a user account on this computer, just over write the user name with your user name and use your password. If you don't have an account, you will need an administrator to unlock it for you.
Sounds like a new laptop, why not read the instructions that came with it? Usually the default password like that would be blank. After you logon you can change the option to provide a user in account management.