cli.php

<?php
require_once __DIR__.'/vendor/autoload.php';
require_once __DIR__.'/RandomCommand.php';

use Symfony\Component\Console\Application;


$console = new Application();
$console->add(new RandomCommand());

$console->run();

RandomCommand.php

<?php

use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Helper\ProgressBar;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;

class RandomCommand extends Command{
    protected static $defaultName = 'test:show-random';
    public function configure(){
        $this->setDescription('Ein Programm welche Zufallszahlen generiert');
        $this->addArgument('maxNumber',InputArgument::OPTIONAL,'Maximale nummer die generiert wird',42);
    }
    public function execute(InputInterface $input,OutputInterface $output){
        
        $output->writeln("Programm start");
        $max = $input->getArgument('maxNumber');
        
        $randomNumber = random_int(0,$max);

        $verboseOutput = $output->section();
        $normalOutput = $output->section();

        $progressBar = new ProgressBar($normalOutput,10);
        for($i = 0;$i<10;$i++){
            sleep(1);
            $verboseOutput->overwrite("ich zähle ".$i,OutputInterface::VERBOSITY_VERBOSE);
        $progressBar->advance();
        }
        $progressBar->finish();

        $output->write("\nIch habe lange nachgedacht und die Antwort lautet: ".$randomNumber);
       return Command::SUCCESS;
    }
}

To initialize usage of symfony console:
composer require symfony/console