Failed Journal Service

I have Ubuntu 18.04 LTS and in the middle of nothing my system behaved strange ... man command didn't work and so on ...
I made a reboot and got output from Grub 2.02

Ubuntu
Advanced options for Ubuntu
System setup

I chose first option and got error 'Failed to start Journal Service' ...
After that the system continued to print a lot of messages ... don't know how to get a logfile so I attached a photo.

How can I save my system or is it lost?

OK ... I managed to get the command prompt from Grub
When I gave the command (as suggested in error message): 'systemctl status systemd-journald.service'
I got following: 'System has not been booted with systemd as init system (PID 1). Can't operate'

Anyone? I can't be the first one in Ubuntu community that encountered this ...