hi how to login addministrator account in windows 7

Hi Shrikant, If you look at the right-hand side panel you will see many related topic questions on this which have been answered. E.g. The one called "Windows 7 administrator"

Enable / Disable the Local (Hidden, Built-In) Administrator Account in Windows 7 Many people familiar with prior versions of Windows are curious what happened to the built-in Administrator account that was always created by default. Does this account still exist, and how can you access it? Reset Windows Administrator Account Password