Pop os dual boot Grub install

1. sudo apt install grub-efi grub2-common grub-customizer
2. sudo grub-install

3. sudo cp /boot/grub/x86_64-efi/grub.efi /boot/efi/EFI/pop/grubx64.efi
   Currently the grub file has basically nothing inside and its needed to be generated via grub-customizer

   Open grub-customizer from applications/activities.
   After opening grub-customizer click Change Environment
   In the OUTPUT_FIle change the value to:

/boot/efi/EFI/pop/grub.cfg

Select save this configuration
Click Apply
Reboot your system

another way, use systemd, this the pop os default.

Commands:
sudo fdisk -l
(note first efi partition block number)
sudo mkdir /mnt/windows

sudo mount /dev/(urwindowsefiblock) /mnt/windows

sudo cp -r /mnt/windows/EFI/Microsoft /boot/efi/EFI

sudo ls /boot/efi/EFI
(above command to check if copied)

( add timeout to see the boot menu)
sudo nano /boot/efi/loader/loader.conf

add these two lines
timeout 5
console-mode max

Third way, for latest 22.04

sudo apt update

sudo apt install os-prober

sudo os-prober

sudo apt install grub-efi grub2-common

sudo add-apt-repository ppa:danielrichter2007/grub-customizer

sudo apt update

sudo apt install grub-customizer

sudo grub-install

sudo update-grub

sudo cp /boot/grub/x86_64-efi/grub.efi /boot/efi/EFI/systemd/systemd-bootx64.efi