When installing Ubuntu on my laptop I can choose from the boot up options:
USB device (UEFI)
I will install it on a used laptop (which has Ubuntu 18.04 already installed). As I know UEFI also holds part of kernel on the Boot partition of the SSD.
My goal is to completely wipe the previous Ubuntu installation (since I bought a used PC and don’t trust the installation).
Which boot up option should I choose? Will starting USB stick in UEFI mode preserve GRUB or Kernel on SSD or use it for the boot purpose or will it erase the whole SSD including boot partition?