The following packages have unmet dependencies:
software-properties-kde : Depends: python3-software-properties (= 0.96.24.32.11) but 1.8.8 is to be installed
E: Unable to correct problems, you have held broken packages.
Try to install python3 from the bionic from bionic-updates
I had issues after installing Kali Linux with apt not working, ended up there were no repositories in the apt sources list, added the following line and did an apt-get update and everything started working.
Add this line to /etc/apt/sources.list
deb http://http.kali.org/kali kali-rolling main non-free contrib