cant bring system back to life

[Daniel]

 First I install Ubuntu, than change desktop to xfce because I dislike Unity. Than I tried to change the directory in thunderbird to /dev/sda2 but thunder bird says no rights to do so. Tunar also say no rights to write. after change the fstab from -ro to -rw the system doesn't restart. Trying to change the fstab from the live system wont work, the drive can not be found.

After all I decided to reformat the drive an install ubuntu again.
Than happens this.

Information:
In my last try the disk was partitioned in two drives sda2 and sda5.
Drive sda2 for Files and sda5 for the System. I have no idea why there was no sda1, sda3 and sda4.
120 GB SSD with 30 GB for System and 40 GB for Files, 50 GB nothing

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubiquity 18.04.14.12
ProcVersionSignature: Ubuntu 5.0.0-23.24~18.04.1-generic 5.0.15
Uname: Linux 5.0.0-23-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: amd64
CasperVersion: 1.394
Date: Thu Sep 19 22:28:17 2019
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd quiet splash --- maybe-ubiquity
LiveMediaBuild: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)