Your Kali Linux
sources.list is wrong which is why you are getting that error. You have mixed a older Debian repository with a Kali repository and you have not entered the entries correctly. Your
sources.list should match the Kali Linux documentation:
deb http://http.kali.org/kali kali-rolling main non-free contrib
It needs to be exactly as shown here. You can use a different mirror (listed here) or as well include the source package repository. (
deb-src http://http.kali.org/kali kali-rolling main non-free contrib)
After you have edited your
source.list to be exactly what is pointed out in the documentation, nothing more, then you should be able to run
apt update and
apt upgrade without any issues.
Now when it comes to software center, please refer to this page of the Kali Linux documentation.
While Kali Linux is architected to be highly customizable, don’t expect to be able to add random unrelated packages and repositories that are “out of band” of the regular Kali software sources and have it Just Work. In particular, there is absolutely no support whatsoever for the apt-add-repository command, LaunchPad, or PPAs. Trying to install Steam on your Kali Linux desktop is an experiment that will not end well. Even getting a package as mainstream as NodeJS onto a Kali Linux installation can take a little extra
Do not expect to be able to install just any piece of software in Kali. If it is not already installed or was not specifically written to operate in Kali Linux it will most likely not work. Furthermore if you add third-party, non-Kali Linux repos you are liable to break your install.
The Software center that I believe you are referring to is simply a graphical front end to your package manager. It is not necessary and if you believe it to be necessary to your Kali Linux install then Kali Linux might not be the right distro for you. Almost every single tool that Kali Linux comes with has a version available for Windows, macOS, or any other Linux distro.