[WiFi][ArchLinux] Activate wifi

1. Install Package
sudo pacman -S network-manager-applet


2. Start daemon && start Daemon at the booting time.
sudo systemctl enable NetworkManager
sudo systemctl start NetworkManager

Created symlink from /etc/systemd/system/dbus-org.freedesktop.NetworkManager.service to /usr/lib/systemd/system/NetworkManager.service.
Created symlink from /etc/systemd/system/multi-user.target.wants/NetworkManager.service to /usr/lib/systemd/system/NetworkManager.service.
Created symlink from /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service to /usr/lib/systemd/system/NetworkManager-dispatcher.service.

Reference:
How to Activate Wireless on Arch Linux