There is a widely reported problem with laptop keyboards in the October and November updates.
For testing purposes, if your keyboard is not working when you start your laptop, on the login window, click the Power icon at the bottom right and choose to restart the laptop, is the keyboard then working after the restart?
If so, in Windows, use this method to disable Fast Startup to test if the keyboard is working when you start your laptop.
Open the old Control Panel (not the settings app)
At the top of the old Control Panel, set view to icons
Open Power Options
On the left, click 'Choose what the power buttons do'
At the top right, click 'Change settings that are currently unavailable'
Under 'Shutdown settings' disable 'Turn on fast startup'
Save that and close Control Panel