This article shows how to enable Built in administrator Account in windows 10 PC’s.
The hidden built-in elevated “Administrator account” is a local account that has full unrestricted access rights to the computer.UAC Prompts would be disabled and the user using it would have full administrative access:

So without wasting time here is the tutorial:

1. Open an elevated Command Prompt by Right clicking the start button and selecting Command Prompt(admin)
2. Type in the following without quotes:

   “

   net user administrator /active:yes“

   (Remember the space after administrator)

3. To add a password use the following
   net user administrator password /active:yes
    –Replace  password  with the actual password.
   
4. Disable:To disable the administrative account use the following command:                        net user administrator /active:no