Windows 7 has released with several version, beginning windows 7 Starter into Windows 7 ultimate. Which distinguishes between the versions is its completeness. In the version of windows 7 starter, home basic and home premium, there is no feature or group policy editor gpedit.msc.
In order for the windows starter, home basic and home premium are features of group policy editor, then you can add it by install the group policy editor installer. You can download it on the download link below.
This file is a ZIP file, extract it using WinRAR or 7-Zip. Run the extracted setup.exe file and you'll be able to access gpedit.msc command via RUN or startmenu search box.