Dual boot Linux Lite 3.4 and openSUSE-Leap-42.2

[TMG1961]

Now the question is how to make sure that both systems do boot after OPenSuse is installed.

Haven't installed OpenSuse myself in a few years so don't remember steps in its installer, but it likely gives you option for where to install grub boot loader.  If you want OpenSuse to control booting, have it install to MBR of drive (eg. /dev/sda).  If you want LL to remain in control, have OpenSuse's grub installed to it's root partition (eg. /dev/sda2), or not at all if that's an option.  If you choose the latter you'll need to update grub in LL before the choice to boot OpenSuse appears on the grub menu.  Just run sudo update-grub in an LL terminal to do that and next reboot will have it listed.

Installed Opensuse, when i start laptop it goes straight to linux lite without a menu. I ran sudo update-grub but still no menu to choose Linux Lite or Opensuse