Credentials need to be created manually via System Manager, and with a credential in place, you can then use the Get action to pull the user name and password into the process. However this will only work if the credential's access rights will allow you to use the credential. If your BP role, process name and PC name do not comply with the access rights, any attempt to use the credential will result in an exception.'Set' and 'Generate and Set' are methods for dynamically updating the values stored in the credential - you would only use these if you wanted to have your robot maintain application passwords.