How do I increase the distance/space between a div and a navbar using bootstrap?

I'm a very beginner in bootstrap, but I'm struggling to learn the basic things and still couldn't find the answer to my problem. My question is: how do I increase the distance/space (I don't know whether it's margin or padding) between a div and a navbar? Please, if possible, see my code below. Thanks in advance!

<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">

<style>
.marcador {
border: 1px solid red;
}

.foto {
border: 1px solid blue;
height: 500px;
margin: 15px;
}

.textobio {
border: 1px solid yellow;
margin: 15px;
}
</style>

<!-- menu -->
<nav class="navbar navbar-expand-sm bg-light">

    <div class="container">

        <a href="index.php" class="navbar-brand">
            Spotify
        </a>

        <ul class="navbar-nav">

            <li class="nav-item">
                <a class="nav-link" href="?name=galeria">Galeria</a>
            </li>

            <li class="nav-item">
                <a class="nav-link" href="?name=biografia">Biografia</a>
            </li>

            <li class="nav-item">
                <a class="nav-link" href="?name=contato">Contato</a>
            </li>

        </ul>

    </div>

</nav>
<!-- end of menu -->


<!-- picture & bio -->
<div class="container marcador">

    <div class="row">

        <div class="col-md-4 foto">
            <img class="img-fluid" src="no-picture-yet">
        </div>

        <div class="col-md-7 textobio">
            Some text.
        </div>

    </div>

</div>
<!-- end of picture & bio -->