Note that macOS already has a highly effective, configurable passport generator. But also note that no computer-specific password generator is entirely random, only what is called 'pseudo-random'. An actual source of real random information is required for entirely random passwords. That's as easy as bashing around randomly on your computer keyboard and throwing some of the result in with a macOS (or other) generated password. In general, it's useful to mangle one generated password with the results of another in order to ruin predictability.
One online source of entirely random passwords, which use real random data, can be found here: