EntrepriseSignupType.php

<?php

namespace App\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\Form\Extension\Core\Type\ChoiceType;

use App\Form\Type\FormuleChoiceType;

class EntrepriseSignupType extends AbstractType
{
	public function buildForm(FormBuilderInterface $builder, array $options)
	{
		$builder
			->add('formule', FormuleChoiceType::class)
		;
	}
}

FormuleChoiceType.php

<?php

namespace App\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\OptionsResolver\OptionsResolver;
use Symfony\Component\Form\Extension\Core\Type\ChoiceType;

class FormuleChoiceType extends AbstractType
{
    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults(array(
            "choices" => array(
					"Radin"     => 1,
					"Pas riche" => 2,
					"Engagé"    => 3,
					"Crésus"    => 4,
				),
				"multiple" => false,
				"expanded" => true,
        ));
    }

    public function getParent()
    {
        return ChoiceType::class;
    }
}

index.html.twig

{% extends 'base.html.twig' %}

{% block formulechoice_widget %}
    {% spaceless %}
        {% if expanded %}
            <div {{ block('widget_container_attributes') }}>
            {% for child in form %}
                {{ form_widget(child) }}
                <h1>Coucou</h1>
                {{ form_label(child) }}
            {% endfor %}
            </div>
        {% else %}
            {# just let the choice widget render the select tag #}
            {{ block('choice_widget') }}
        {% endif %}
    {% endspaceless %}
{% endblock %}

{% block body %}
	{{ form_start(form) }}
	    {{ form_label(form.formule) }}
		{{ form_errors(form.formule) }}
		{{ form_widget(form.formule, {'attr': {'class' : 'd-flex justify-content-around'}}) }}
		{{ form_help(form.formule) }}
	{{ form_end(form) }}
{% endblock %}