GUI feature missing from full ubuntu installation 18.04

Question

I encountered multiple problems installing libraries (to python) that have many dependencies..at some point I think it just crashed,

now it boots only to terminal window starting from login. Meanwhile, I relocated to many places, so the internet is lost.

Can anyone guide me:

1. to connecting the internet, (I can't get the ip route to return anything, ifconfig to work without net-tools that must be installed using sudo apt, which requires internet..oh the vicious cycle)

   resolved with the command

   nmcli dev wifi connect <mySSID> password <myPassword>
   

2. reviving the GUI features that normally worked .. I didn't install server version obviously.

   Tried:

   sudo apt-get install compizconfig-settings-manager
   

   from Fix user interface (Ubuntu Unity) disappearing problem after upgrade to Ubuntu 16.04

DISPLAY:=0 ccsm & directs me to a library gtk under python2.7. Returned a msg in line with Nonetype cannot bring default screen

when running sudo apt upgrade --fix-missing

Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/g/gdm3/libgdm1_3.28.2-0ubuntu1.3_amd64.deb 404 Not Found & the like, grub2

Answer 1

First get your packages sorted out

If you are getting errors downloading packages, you need to enable mirrors:

How can I get apt to use a mirror close to me, or choose a faster mirror?

Then run:

sudo apt update && sudo apt upgrade --fix-missing

This should fix any broken things with apt and your package library.

Next, reinstall the GUI

sudo apt install --reinstall ubuntu-session gdm3
sudo dpkg --configure -a
sudo dpkg-reconfigure gdm3

Start the X server

You can now reboot or start the server manually to make sure it works:

startx