Let me update this code so it works better
<form onsubmit="location.href='http://yourURL.com/' + document.getElementById('myInput').value; return false;">
<select class="w-input yourclassnocaps" id="myInput" required >
<option value="" disabled selected>Select a page...</option>
<option value="yourpageslug">Your Page Name</option>
</select>
<input class="w-button yourclassnocaps" type="submit" />
</form>