Hello everyone. I have a HP Pavilion Notebook. I had dual boot Ubuntu 18.04 and Windows10. Everything was working fine but all of a sudden when i boot my laptop to navigate to windows option on Grub it was not working, I even tried booting through bios boot option none of the keys are working on grub. I directly boots to ubuntu after the countdown and after that the keyboard is working properly. Please help!!!

I suppose you have not reconfigured grub recently, have you? Still, check the timestamp of /boot/grub/grub.cfg (I am not sure if this path is 100% correct). How recent is it? Also share your /etc/default/grub; I am particularly interested in GRUB_TERMINAL_INPUT.

If /etc/default/grub looks good, use grub_mkconfig to recreate grub.cfg and reboot.

By the way, an internet search for grub keyboard not working yields an astonishing number of results. Have a try.

Do you have an external keyboard you could try?

/* etc/default/grub */

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
GRUB_TIMEOUT_STYLE=hidden
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

This is not a Kernel issue.

Could be a setting in your bios or possibly some issue with your grub. I'd look at the bios first, often there is an option to enable keyboard/interface before boot (OS).

One experience I had might be relevant. On a new build with an Asus motherboard, if I hit the down key on the grub boot selection screen, grub would not move down to the next selection. If I hit the down key again, grub would move down two entries. I soon discovered that even though grub would not move down one entry when I hit the down key the first time, grub was at that entry right below the first and if I hit the Enter key, grub would boot that entry anyway. This condition only occurred if I had a second monitor connected to the system. With only one monitor, grub behaved normally. Also, like you, the keyboard worked normally in the bios setup.

Bottom line, even though grub is not moving down when when you hit your down arrow key, it may actually be at the next entry.

I recently, figured it out it was not an GRUB issue. I have removed my Ubuntu partition and trued installing it back but the keyboard was not working on bios as well. When my Windows boots up i cannot use my keyboard there to enter password as well, i have o used on screen keyboard or an external keyboard. Please give me a solution for it. How can i configure it that everything goes back to normal.

You could try to reset the bios settings if you know that it will do any other damage. That is, if you don't have any special settings in there. Also if you name the bios/uefi and the version number, someone might help with the specific setting in there to try to solve it.

BIOS Mode:- UEFI
BIOS Version:- Insyde F.90

As I said, perhaps someone can help with it specifically. But as I see it, you could try to reset the settings in your bios to see if it helps. If you have it in UEFI mode and did no special changes or you know what changes they were, it should be safe to reset the bios settings and revert necessary changes (legacy mode??) etc afterwards. There are two ways to reset it, the soft mode is to reset the settins, and the hard mode is a hard reset motherboard version.

But resetting the settings might help. If you feel confident about it, go ahead and try. If not, wait for further assistance here. Perhaps someone knows the uefi version you use and any relevant settings in there and can point you to them.

You get into the bios by pressing F10? But then keyboard is not working? What if you press F9 when you are in the bios?

Maybe this helps:
https://www.youtube.com/watch?v=2T6Y03295J4
https://www.youtube.com/watch?v=qpiGUojtr3E

If the problem persists, do you have a USB keyboard available?