There is no general way to remove software. How software is removed, depends on how it is installed. And Linux in general knows many different ways to install software.

• In its simplest way, "installing" software can be a matter of copying the program files in a directory on the drive, and launching the executable from the directory where it resides. Uninstalling then boils down to deleting that directory.


• In its most complex way, software can be installed by compiling it from the source code. Compiling means converting the source code readable by humans to machine code that is understood by your computer processor. The complexity usually does not result so much from the compiling itself, but from the need to make sure that all other components the software depends on, i.e., the dependencies, are already available on the system. For uninstalling, you depend on the kindness of the developper. If he/she did not provide an uninstall script, your only way of uninstalling will be to check where the install script installed the files, and manually remove these yourself.


• Linux distributions automate package management for the user by providing precompiled and autoinstalling packages. This allows the user to install software that has been tested for the distribution by using the dedicated tools, from command line, i.e. using apt, or the older apt-get, or aptitude on Ubuntu, to graphical interfaces like Synaptic Package Manager, or modern and very easy interfaces like the Ubuntu store. Different families of Linux systems use their own systems: Debian and derivatives including Ubuntu and Mint use the APT system, Fedora and derivates uses the RPM package manager, Arch and derivates use the pacman package manager system. All these systems offer an easy way to uninstall the software that was installed using that system.

• To make matters more complicated, "universal" package formats emerged in recent years. These are packaging formats developed to be used across distributions, i.e. package only once and install on many different linux systems, Ubuntu, Fedora, Arch, ... alike. Snap is developed by the Ubuntu developers and is enabled by default. Then there is also Flatpak. Both formats again allow for easy installation and uninstall using their dedicated tools, or, very easily, through the Software center if the Snap and Flatpak integrations are installed.


• There is also the AppImage format, a third way for providing "universal packages". These are single files, which can be run in many Linux systems by making them executable. "Installing" means just downloading the file, to uninstall, just delete the file.

Of course, this is the general answer to the general question you stated in the question title and later in the body of your question. It is aimed to provide you some conceptual overview.

For your specific problem, i.e., having several icons in your application overview or application menu, you understand from the explanation above that how to remove the actual software, i.e., all program files, depends on the way you have installed the program. The menu entries are represented by little text files with the extension .desktop. If all else fails, you can remove these entries by deleting these little files, which are installed in specific directories, /usr/share/applications for applications installed using the APT system.

To remove these, it may be easier to install a graphical utility like Alacarte or Menulibre, which allow to remove and edit application menu entries.