Kubuntu will not load, nor restore

Hello everyone,
First post here.....

I have been running Kubuntu 20.10 for a year or so on my Samsung Ultra book.

When installing, I partitioned the HDD and installed Kubuntu in a small directory and the rest of the drive I used for my files.

Lately the laptop has been warning me that I was low on space in my home directory.
I tried to remove some unused apps, Delete files etc, but the warning kept coming back so I installed BleachBit.
I cleaned a bit at the time, trying to get more space, but suddenly Kubuntu said I had 0 space left and it frooze.
I had to hard 'Power off' but then have not been able to get back into it.

Starting it normally brings the log-in screen, but then it freezes there.

Booting from the live USB brings two errors:

1. Failed to start Ubuntu live CD installer and
2. Failed to start Simple Desktop Display Manager

Pressing Esc on booting brings the Grub menu, I get a long list of possible commands, I tried a few, but nothing happens.

I am writing from my tablet, I took some screen shots of the laptop, but I am not able to upload, possibly because I am new on the forum...

Can anyone help me with some advice?

Many thanks