I'D found how to resolve the problem which is How to add a DSN from Database in Transport with Symfony Mailer...

I'd created a service like that:

namespace App\Services;

use Doctrine\ORM\EntityManagerInterface;
use App\Entity\IdentifiantMailing;
use Symfony\Component\Mailer\Mailer;
use Symfony\Component\Mailer\Transport;
use Symfony\Component\Mime\Email;
use Symfony\Component\Mime\Part\DataPart;
use Twig\Environment;

class EmailSender
{
    private $em;
    private $adresse;
    private $mdp;
    private $serveur;
    private $port;
    private $from;
    private $twig;

    public function __construct(EntityManagerInterface $em, Environment $twig)
    {
        $this->em = $em;
        $IdentifiantRepos = $this->em->getRepository(IdentifiantMailing::class);
        $identifiant = $IdentifiantRepos->findAll();

        $this->adresse = $identifiant[0]->getAdresse();
        //$this->adresse = rawurlencode($this->adresse);
        $this->mdp = $identifiant[0]->getMotDePasse();
        //$this->mdp = rawurlencode($this->mdp);
        $this->serveur = $identifiant[0]->getServeur();
        $this->port = $identifiant[0]->getPort();
        $this->from = $identifiant[0]->getDepuis();
        $this->twig = $twig;
    }

    public function sendEmail($sender, $destinataire, $subject, $pathTwigTemplate, $PJ, $context)
    {
        $dsn = sprintf('smtp://%s:%s@%s:%d', $this->adresse, $this->mdp, $this->serveur, $this->port);

        $transport = Transport::fromDsn($dsn);
        $mailer = new Mailer($transport);
        
        if(null===$context){ 
            if(null===$PJ){ //$context est nul et $PJ est nul

                $email = (new Email())
            ->from($sender)
            ->to($destinataire)
            ->subject($subject)
            ->html($this->twig->render($pathTwigTemplate));
            $headers= $email->getHeaders();
            $headers->addTextHeader('X-Auto-Response-Suppress', 'OOF', 'DR', 'RN', 'NRN', 'AutoReply');

            } else {//$context est nul et $PJ existant

                $email = (new Email())
            ->from($sender)
            ->to($destinataire)
            ->subject($subject)
            ->html($this->twig->render($pathTwigTemplate))
            ->attachFromPath($PJ);
            $headers= $email->getHeaders();
            $headers->addTextHeader('X-Auto-Response-Suppress', 'OOF', 'DR', 'RN', 'NRN', 'AutoReply');
            }
        } else {
            if(null===$PJ){ //si $context est existant et $PJ est null

                $email = (new Email())
            ->from($sender)
            ->to($destinataire)
            ->subject($subject)
            ->html($this->twig->render($pathTwigTemplate, $context));
            $headers= $email->getHeaders();
            $headers->addTextHeader('X-Auto-Response-Suppress', 'OOF', 'DR', 'RN', 'NRN', 'AutoReply');

            } else {//si $context est existant et $PJ est existant

                $email = (new Email())
                ->from($sender)
                ->to($destinataire)
                ->subject($subject)
                ->html($this->twig->render($pathTwigTemplate, $context))
                ->attachFromPath($PJ);
                $headers= $email->getHeaders();
                $headers->addTextHeader('X-Auto-Response-Suppress', 'OOF', 'DR', 'RN', 'NRN', 'AutoReply');
            }
        }

        $mailer->send($email);
    }
}

An I use this like That:

namespace App\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Attribute\Route;
use App\Services\EmailSender;

final class TestSymf7Controller extends AbstractController
{
    #[Route('/test', name: 'test')]
    public function index(): Response
    {
        return $this->render('test/index.html.twig', [
            'controller_name' => 'TestSymf7Controller',
        ]);
    }

    #[Route('/testmessage', name: 'testmessage')]
    public function sendEmail(EmailSender $emailSender): Response
    {
        /*******************************Preparation de l'email***************************
        ******************to consume messenger in dev run 
        *******************php bin/console messenger:consume async -vv**************************************/
        //must be not real sender for wouldn't answering or may be real for no spams emails client routing ???
        $sender = '[email protected]';
        $destinataire = '[email protected]';
        $subject = 'Exemple d\'e-mailtest1';
        //must be in /templates/emails/..
        $pathTwigTemplate = '/emails/inscriptionok.html.twig';
        //must be in /public/piecesemails/..
        //$PJ = '/public/piecesemails/pj.pdf';$PJ = $this->getParameter('kernel.project_dir') . $PJ;
        // ou de type $PJ = null 
        $PJ = null;
        //$context de type array ou = null
        $context = ['email' => '[email protected]'];
        //$context = null;
        $emailSender->sendEmail($sender, $destinataire, $subject, $pathTwigTemplate, $PJ, $context);
        /************************************email envoyé********************************/
        return new Response(
            '<html><body>OK Done !</body></html>'
        );
    }
}

It Run...

For more the Entity is like that :  

namespace App\Entity;

use App\Repository\IdentifiantMailingRepository;
use Doctrine\ORM\Mapping as ORM;


#[ORM\Entity(repositoryClass: IdentifiantMailingRepository::class)]
class IdentifiantMailing
{
    #[ORM\Id]
    #[ORM\GeneratedValue]
    #[ORM\Column(type:"integer")]
    private $id;

    #[ORM\Column(type:"string", length:255)]
    private $adresse;

    #[ORM\Column(type:"string", length:255)]
    private $motDePasse;

    #[ORM\Column(type:"string", length:255)]
    private $serveur;

    #[ORM\Column(type:"string", length:6)]
    private $port;

    #[ORM\Column(type:"string", length:255)]
    private $depuis;

    #[ORM\Column(type:"text")]
    private $message;

    public function getId(): ?int
    {
        return $this->id;
    }

    public function getAdresse(): ?string
    {
        return $this->adresse;
    }

    public function setAdresse(string $adresse): self
    {
        $this->adresse = $adresse;

        return $this;
    }

    public function getMotDePasse(): ?string
    {
        return $this->motDePasse;
    }

    public function setMotDePasse(string $motDePasse): self
    {
        $this->motDePasse = $motDePasse;

        return $this;
    }

    public function getServeur(): ?string
    {
        return $this->serveur;
    }

    public function setServeur(string $serveur): self
    {
        $this->serveur = $serveur;

        return $this;
    }

    public function getPort(): ?string
    {
        return $this->port;
    }

    public function setPort(string $port): self
    {
        $this->port = $port;

        return $this;
    }

    public function getDepuis(): ?string
    {
        return $this->depuis;
    }

    public function setDepuis(string $depuis): self
    {
        $this->depuis = $depuis;

        return $this;
    }

    public function getMessage(): ?string
    {
        return $this->message;
    }

    public function setMessage(string $message): self
    {
        $this->message = $message;

        return $this;
    }
}