I want to run this hello world program which need C++23

import std;

int main()
{
    std::cout << "Hello, World!n";
}

I’m on a mac and i enter this into the terminal:

g++-13 -std=c++2b hello_world.cpp -o hello

also tried with -std=c++23

However it gives the error: C++20 ‘import’ only available with ‘-fmodules-ts’, which is not yet enabled with ‘-std=c++20’

Why is it still on C++20?