Output to the Frontend
Visual Page Selector is an page inputfield for normal ProcessWire Page Fieldtypes. Hence, it has no API of its own. To output the content of your page fields, use the normal ProcessWire approach. If it is a multiple page field, iterate through it since it will be a PageArray. Each item in that PageArray will be a Page object.
Examples
Assuming you created a multiple page field called gallery, you can loop through it for a given page as shown below.
<?php $items = $page->gallery;// returns a PageArray. Needs to be looped through foreach ($items as $item) { echo $item->title; // output images in a single-item image field called 'image' in these pages $img = $item->image echo "<img src='" . $img->size(100,75)->url . "'><br>"; }