Missing system settings in Ubuntu, how to get it back?

Question

Graphic shells

Good afternoon, the crux of the matter is that after launching Ubuntu 20.04 with a graphical shell, the user's network "fell off", while both connecting directly and WiFi, there were no updates, connection attempts were unsuccessful.
Also, the main problem itself is that there is no way to enter the network parameters, they are simply not called up, the usual settings are also not called up, what if someone came across this?

Answer 1

You are unobtrusively invited to the second level - "acquaintance with the console".

Answer 2

sudo apt-get install gnome-control-center
sudo apt-get install unity-control-center

Answer 3

I would try to create a new user in the system and transfer the necessary settings from the old profile there.

Answer 4

sudo apt install ubuntu-desktop