The new Start menu is something that many are looking forward to seeing in Windows 10. As of build 10125 (which has only been released in screenshots), it is finally possible to customize the Start menu, adding or removing items that are on its left side. 
Below we explain how it can be done.
Microsoft has added some customization options to the Start menu. The new options from the Settings app allow the end user to customize the items that appear in the lower left area of the Start menu. Items like Documents, HomeGroup, User Profile, and more can be easily added to the new menu.
To customize the Start menu in Windows 10, you need to open the Settings app. Then go to Personalization / Start:
Click Customize List. 
On the next screen you will be able to choose which items will appear on the Start menu:
The Start menu customization was added as a feature in Windows 10 build 10125, which is not yet available. Later, it is expected to be released to Windows Insiders.
