Gfilui

I asked how I can install my nvidia card and got forwarded to How do I install the Nvidia drivers?.

So I did the basic commands (ppa, update...) , but nothing seemed to happen. I read the tutorial couple of times, for being a very basic user I dont understand it and I m afraid of making it worse.

$ apt search nvidia - | egrep "^nvidia-[0-9]+/"

gave out

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

nvidia-304/xenial 304.137-0ubuntu0~gpu16.04.1 amd64
nvidia-331/xenial 340.106-0ubuntu0+gpu16.04.2 amd64
nvidia-340/xenial 340.106-0ubuntu0+gpu16.04.2 amd64
nvidia-346/xenial 352.63-0ubuntu3 amd64
nvidia-352/xenial 361.42-0ubuntu2 amd64
nvidia-361/xenial-updates,xenial-security 367.57-0ubuntu0.16.04.1 amd64
nvidia-367/xenial-updates,xenial-security 375.66-0ubuntu0.16.04.1 amd64
nvidia-375/xenial 384.130-0ubuntu0~gpu16.04.1 amd64
nvidia-384/xenial 384.130-0ubuntu0~gpu16.04.1 amd64
nvidia-387/xenial 390.48-0ubuntu0~gpu16.04.3 amd64
nvidia-390/xenial,now 390.48-0ubuntu0~gpu16.04.3 amd64 [installed]
nvidia-396/xenial 396.18-0ubuntu0~gpu16.04.2 amd64

and

$ ubuntu-drivers devices gave out literally nothing.

$ sudo lspci | grep -i vga gave out:

00:02.0 VGA compatible controller: Intel Corporation 4th Generation Core Processor Family Integrated Graphics Controller (rev 06)

(which might be my onboard graphic... (?))

$ sudo lshw -C display gave out:

*-display 
 Beschreibung: VGA compatible controller
 Produkt: 4th Generation Core Processor Family Integrated Graphics Controller
 Hersteller: Intel Corporation
 Physische ID: 2
 Bus-Informationen: pci@0000:00:02.0
 Version: 06
 Breite: 64 bits
 Takt: 33MHz
 Fähigkeiten: msi pm vga_controller bus_master cap_list rom
 Konfiguration: driver=i915 latency=0
 Ressourcen: irq:28 memory:f7800000-f7bfffff memory:e0000000-efffffff ioport:f000(Größe=64) memory:c0000-dffff

How can I fix this?

There is, indeed, a "control panel" in Ubuntu. It's called System Settings. You can launch most applications by typing part of the name or description in the Unity Launch Button. It's on the top of the Sidebar Launcher.

Once you have brought up System Settings, click on Software & Updates. Then click on the Additional Drivers Tab.

The app will analyze your configuration and give you the results you are asking for. This will include a list of your installed drivers. It's also flag a recommended driver based on the drives you have installed. And, of course, as you have asked, it will show you the driver that you are currently using. Usually, if there is a detected problem with the driver, you'll see a message to that effect.

You can also use this GUI app for changing and testing some of the other drivers you have installed.

The links in your question show you resources for locating and installing Nvidia drivers. The installation for installing the drivers are usually in the form of a PPA provided by the vendor. At times it will be a file that is run from the commandline. They also provide *.deb files, which can be installed by clicking on them.

If you install a driver that is causing problems getting your GUI screen, you can use the commandlines (which is also included in the links you posted) from a terminal console (Ctrl+Alt+F2 to fix it by running the command line version of the drivers install utility.

The commanline version is:

Check for available drivers

$ ubuntu-drivers devices

Install a different driver

$ sudo apt install nvidia-###

(The ### is replaced by the version of the available drivers you have on your machine.)

Show which driver is currently in use

$ lspci -nnk | grep -i vga -A3

Driver install commands are included in the Links you posted in your question, plus this link - Switching NVidia Drivers.