Installing Windows 10 over Linux- Having Serious Installation Issue

[Animesh_Sahu]

Its not like windows first linux second, if you ever want to install windows after linux you just have to run grub-install and update-grub, in order to make the linux efi entries up on the boot menu:

@Animesh_Sahu

Restoring the EFI entries is as easy as running these from live boot:

mount /dev/<rootpart> /mnt
mount /dev/<efipart> /mnt/boot/efi
for i in /dev /sys /proc; do mount --bind $i /mnt$i; done
chroot /mnt
sudo grub-install
sudo update-grub

for anybody wanting to upgrade BIOS after installing any linux distro.