When you first start the laptop, can you get into BIOS or load in "Safe Mode"? I ask because sometimes it is not until you get to Windows that the keyboard will not work, but will prior to that.
If you can get it to load in "Safe Mode" then something is on the computer that needs removing.
How to enter "Safe Mode" when booting the computer.
In Windows 8 and 10 ...
As your computer restarts, press F8 (possibly a few times) to enter "Safe Mode"
a. Press the "F4" key to Enable "Safe Mode".
(The computer will then start in "Safe Mode" with a minimal set of drivers and services.)
b. Press the "F5" key to Enable "Safe Mode" with Networking.
( Once "Safe Mode" with Networking starts, Windows is in Safe Mode, with additional network and...