<fieldset>
    <legend>Course registration</legend>

    <label for="name">Course name</label>
    <select id="name">
        <option value="flower">Flower taming</option>
        <option value="lion">Lion arranging</option>
    </select>

    <label for="start">Start month</label>
    <input type="month" id="start" name="start"
           min="2018-03" value="2018-05" />
    <span class="validity"></span>

</fieldset>

Output