Or go to the Microsoft site and create a bootable USB with Win 10 on it.  Boot from that USB and follow the prompts to repair Win 10. If that works you won't have to do a clean install and lose your data or have to install all your apps...
I have an inspiron 3470 with windows 10.  At startup it shows the dell logo and then goes to a blue screen with the code 0xc00021a.  Then the computer shuts down.  Is there a way to restart the computer?
blue screen at startup