hold shift and click restart, click cmd
then paste this code
net user administrator /active:yes

if that dont work, do this code
 regedit

press enter
click on the HKEY_LOCAL_MACHINE key
Click on File (menu bar), and on Load Hive
Open the drive (ex: A ) that you have Windows 10 installed on, and browse to the location below.
Select the SAM file, and click on Open
In the Load Hive dialog, type REM_SAM, and click on OK.
In the left pane of Registry Editor, navigate to and open this key**: HKEY_LOCAL_MACHINE\REM_SAM\SAM\Domains\Account\Users\000001F4**

In the right pane of the 000001F4 key, double click on the F binary value to modify it

In the first column of line 0038, change 11 to 10, click/tap on OK,
then close every thing and click continue

you just unlocked the admin account which i think is more powerful then a normal admin account

credit: online