The operating system on every Mac since 2000 has been UNIX with a very
Mac-like appearance. It requires users to log into the computer with an
account, which has a user name and password.
When we prepare a new computer, we NEVER put a password on the main
account. You are welcome to add a password yourself, but we never ever do
that. When you install software, or updates, the computer will ask for
your password.... but you do not have one. Simply click on the 'Next' or
'Go' or 'Continue' button without typing a password. It will carry on and
do what you want.