Ubuntu 18.04.3 LTS tty1
 

the problem begun since I run Jupiter Note, I got some error message, I tried to add package python with matplotlib, so I doing

sudo apt-get purge python3.6

after that I lost my ubuntu desktop and terminal

how to fix my ubuntu, I am worry If do
sudo apt-get install ubuntu-desktop
then all my file will gone

any suggest please help me?

It's unlikely your files will be gone, but you could back them up before installing the desktop.

is there any another solution beside install ubuntu desktop?
or could you give me the guidance step by step for me just make sure I am not do the false step and make all my file will gone.
because is very difficult reinstall all data file.

thank you for your suggestion

I do

Sudo apt-get install ubuntu-desktop

but I have message at the end
depends : foomatic-db-compressed-ppds but it is not going to be installed
..
...
...
Unable to correct problems, you have held broken packages.

what should I do?

I have the feeling that the command outputs more messages with important information. All I know is that you have broken packages, but I don't know which ones and if more details are available.

Here is a lesson for you: Error messages are not necessarily useless. Read them and learn to judge if they are relevant.

You might also want to reinstall Python, if that still works.

If your problem is the fact that you have lost the desktop, the only practical solution apart from checking file by file is installing the desktop. Or simply installing Ubuntu.

Python is fundamental. Many system programs are written in Python these days. Purging it is not a good idea, and I am certain that apt-get purge told you which other packages would be removed.

foomatic is a set of printer drivers for CUPS. Perhaps there is a way to install a partial desktop without CUPS.