Linux apt-get command not found - How to install a package in Arch Linux?

I used this page https://wiki.archlinux.org/index.php/Pacman_Rosetta when I moved to Arch linux, it lists the equivalent commands for various common package managers, including apt and pacman.

For example:

+-----------------------+-------------+----------------+-------------------------+----------------+-----------------+
|        Action         |    Arch     | Red Hat/Fedora |      Debian/Ubuntu      | SLES/openSUSE  |     Gentoo      |
+-----------------------+-------------+----------------+-------------------------+----------------+-----------------+
| Install a package(s)  | pacman -S   | dnf install    | apt install             | zypper install | emerge [-a]     |
| Remove a package(s)   | pacman -Rs  | dnf remove     | apt remove              | zypper remove  | emerge -C       |
| Search for package(s) | pacman -Ss  | dnf search     | apt search              | zypper search  | emerge -S       |
| Upgrade Packages      | pacman -Syu | dnf upgrade    | apt update; apt upgrade | zypper update  | emerge -u world |
| ...                                                                                                               |

First of all, Arch provides a beautiful, well maintained wiki. You may want to read it first before working with Arch. The pre-installed package manager is "pacman".

To install a package from the official repositories, you will need to use it like this:

# pacman -S <package name>

There is also a community maintained version, the Arch User Repository, for packages not part of the official repository.