codeigniter 4 running error first time with xampp

sudo apt install php{your php version}-intl
sudo systemctl restart apache2`

sudo apt install php7.2-intl
sudo systemctl restart apache2

locale_set_default($this->config->defaultLocale ?? 'en');

#locale_set_default($this->config->defaultLocale ?? 'en');

app.locale = "en"

 <div class="heroe">

        <h1>Welcome to CodeIgniter </h1>

        <h2>The small framework with powerful features</h2>

    </div>