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?