gridex.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <link rel="stylesheet" href="ex/bootstrap/css/bootstrap.min.css">
</head>
<body>
    <div class="container">
        <div class="col-sm-6 bg-primary">
            <p>
                This is 1st box
             </p>
        </div>
        <div class="col-sm-3">
            <div class="row bg-secondary">
                <p>
                    This is 2nd box
                </p>
            </div>
            <div class="row bg-success">
                <p>
                    This is 3rd box
                </p>
            </div>
            <div class="row bg-warning">
                <p>
                    This is 4rth box
                </p>

            </div>
        </div>
        <div class="col">
            <div class="row-sm-8 bg-info">
                <p>
                    This is 5th box
                </p>

            </div>
            <div class="row bg-primary">
                <p>
                    This is 6th box
                </p>
            </div>
        </div>
    </div>
</body>
</html>