This should be installed as default in all distro.
Run it with --install, put appimages in ~/Applications and it's done, you'll see all apps in your DE app men
But, if you are willing to use the terminal, then there's appman. Appman is a terminal package manager for handling appimages, which also integrates appimages into the system. It can update appimages, as well as install images that are not found on its package database.