How to install Kdenlive on Kali Linux?

Until this moment, I have installed packages solely on Ubuntu. Now, I am trying Kali Linux,namely uname -v #1 SMP Debian 4.9.18-1kali1 (2017-04-04) A friend, who unfortunately knows less about Linux than me, told me of his problem to install even basic Packages on another Debian distro, though this seems odd, since I heard, that the Repository of Debian is far more bigger than that from Ubuntu. I tried apt install kdenlive apt install audacity apt install blender The fruitlessness of my striving made me modest and so I tried apt install cowsay But even this could not be installed, could you give me an advice how to deal with this?