You are using bootstrap and you want to add datepicker, then you can use the bootstrap-datepicker library. But if you are new then learn to add datepicker in bootstrap.
Follow the codes below
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<meta name="author" content="">
<title>Bootstrap Datepiker</title>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet">
<link href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-datepicker/1.5.0/css/bootstrap-datepicker.css" rel="stylesheet">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-datepicker/1.5.0/js/bootstrap-datepicker.js"></script>
</head>
<body>
<strong>Date : </strong>
<input class="date form-control" style="width: 300px;" type="text">
<script type="text/javascript">
$('.date').datepicker({
format: 'mm-dd-yyyy'
});
</script>
</body>
</html>