sudo dd if=/dev/nvme0n1 of=/mnt/external/hp_elitebook_image/hp_elitebook.img bs=4M status=progress
Before that, you have to find out which disk you want to copy:
lsblk
or
fdisk -l
…and you have to mount external disk where you want to make an img file:
sudo mkdir -p /mnt/external sudo mount /dev/sdb1 /mnt/external