MyProject/app/views/header.php

<div class="row mt-3">
    <div class="col-6">
        <h1><a href="/">Блог</a></h1>
    </div>
    <div class="col-6 text-end">
        <?=$_SESSION['user']['login']; ?>
        <a class="ms-5" href="/user/logout">Выход</a>
    </div>
</div>