Jetson TK1 Pro - First Setup

I received a Tk1 Pro, for automotive development,I’m facing a few problems with it, related to the first use.
Does it come with a basic Linux Tegra version, or do I need to install it?
How do I install it? If possible give me the first required steps to it.
Wich files do I need to download to install it? And how to do so using a Linux host manchine?

I do not have a TK1 Pro, but it is very likely it ships with the same Linux for Tegra (L4T) as the non-Pro JTK1.

L4T is basically just Ubuntu 14.04LTS Linux set up for those boards, plus files for direct hardware access/acceleration. When a JTK1 arrives, it has the Ubuntu portion of L4T R19.2 installed, but the nVidia-specific files reside in the default user directory “~/NVIDIA-INSTALLER”. The script there, “installer.sh” (requires running with sudo), will do the final install of the nVidia-specific files. The logic is that this puts everything on the Jetson which is GPL without user intervention, and then lets the user separately install the non-GPL parts. Typically you will only be able to work in text mode until those files are installed.

L4T R19.2 had many improvements up until the current release, R21.4. It is highly recommended to install R21.4 after you have familiarized yourself with the original install. If you want to do a backup before flashing, you may be interested in cloning the root partition. See:
http://elinux.org/Jetson/Cloning

Note that the NVIDIA-INSTALLER directory contains a full R19.2 install, but the script only unpacks some of the files, it does not run the full installer. The full installer requires a separate x86_64 Linux host. Those files being unpacked would be equivalent to the flash step from an x86_host of “apply_binaries.sh”, which populates those files to a root partition file system. Flash from an x86_64 host is not hard, but takes significant time.

You may see references to JetPack. I do not know if the Pro version works with JetPack, but it may be useful to know that JetPack bundles software. JetPack is not required to flash.