Example: daterangepicker

<html>
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Bootstrap 4 DatePicker</title>
    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
    <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
    <script src="https://unpkg.com/gijgo@1.9.14/js/gijgo.min.js" type="text/javascript"></script>
    <link href="https://unpkg.com/gijgo@1.9.14/css/gijgo.min.css" rel="stylesheet" type="text/css" />
</head>
<body>
    <div class="container">
        Start Date: <input id="startDate" width="276" />
        End Date: <input id="endDate" width="276" />
    </div>
    <script>
        var today = new Date(new Date().getFullYear(), new Date().getMonth(), new Date().getDate());
        $('#startDate').datepicker({
            uiLibrary: 'bootstrap4',
            iconsLibrary: 'fontawesome',
            minDate: today,
            maxDate: function () {
                return $('#endDate').val();
            }
        });
        $('#endDate').datepicker({
            uiLibrary: 'bootstrap4',
            iconsLibrary: 'fontawesome',
            minDate: function () {
                return $('#startDate').val();
            }
        });
    </script>
</body>
</html>