To install additional software packages on a Linux system, you can use the package manager specific to your distribution, such as APT, DNF, or Pacman. Use the package manager's command-line interface to search for the desired software package and install it with a single command. Alternatively, you can install software from the source code by downloading the source, configuring the installation options, compiling, and then installing it manually. Some Linux distributions also support third-party package managers like Snap, Flatpak, or AppImage, which offer alternative ways to install software packages not available in official repositories.