sudo useradd -s /bin/bash -m -c "Full Name" user
The command is composed of:
sudo: We need administrator privileges to allow a new user to access the computer.
-s /bin/bash: The shell option. This sets the default shell for this new user.
-m: The make home directory option. This creates a directory in the “/home/” directory, with the same name as the new user account name.
-c “Full Name”: The full name of the new user. This is optional.
user: The name of the new user account. This must be unique. It cannot already be in use for another user.