After you open the Windows 8.1 computer, select your account and type the password in the provided field (). You don't need to enter the username anywhere because the computer memorizes it automatically, when you create a new user account. If you want to change the password, open PC Settings, click the Accounts menu and select Sign-in options. Click Change, type your current password and then the new one. If you want to create a new user account, follow the instructions provided by Microsoft Support team.