It’s mostly the package manager, but a lot of distros share the same package manager. Like Debian and Ubuntu both use APT. Arch and Manjaro both use pacman. Most distros you install a traditional way with a graphical installer, but arch you actually install and configure the components manually from the command line. I wouldn’t recommend it for beginners because it is pretty technical, but rather try something else, and come back to arch when you think you might be able to handle it. I think Linux mint is a great starter distro personally. Also you can change the desktop however you like on any system, so choose something that functionally works for you, and then you can mod it to be what you want.