Execute:

php vendor/bin/codecept bootstrap

This creates the global configuration file codeception.yml, the tests/ directory, and the default test suites.

Generate your first acceptance test. Acceptance tests emulate the behavior of a real user visiting your site.
Acceptance Testing Guide »

php vendor/bin/codecept generate:cest Acceptance First

It's now time to write your first test. Edit the file we've just created tests/Acceptance/FirstCest.php

<?php

class FirstCest
{
    public function frontpageWorks(AcceptanceTester $I)
    {
        $I->amOnPage('/');
        $I->see('Home');
    }
}
                

It will check if your frontpage contains the word Home.

Please make sure your local development server is running.  Put application URL into:  tests/Acceptance.suite.yml 

actor: AcceptanceTester
modules:
    enabled:
        - PhpBrowser:
            url: {YOUR APP'S URL}
                

Tests are executed with 'run' command

php vendor/bin/codecept run --steps

This will execute our test with PhpBrowser. It's PHP script that can check HTML page contents, click links, fill forms, and submit POST and GET requests. For tests that require a real browser (e.g. JavaScript) use the WebDriver module.