1)
https://www.dokuwiki.org/plugin:random_page
2) or use some javascript in template
3) if you use this feature on all pages, you can attach random page block in template with PHP code. for example, in page's bottom, or in float sidebar
I have a similar solution for logos in my site
https://comicslate.org. every 10 minutes logo changed from 0 to 8 with step by 1 and it's link changed too, but link isn't numbered. here some code from my template
$rlogo=time() / 600 % 9;
echo '<a href="/';
switch($rlogo){
case 0 : echo 'wiki';break;
case 1 : echo 'sci-fi/freefall';break;
case 2 : echo 'gamer/lwhag';break;
case 3 : echo 'sci-fi/kitty';break;
case 4 : echo 'mlp/apdp';break;
case 5 : echo 'gamer/yafgc';break;
case 6 : echo 'sci-fi/kitty';break;
case 7 : echo 'gamer/gamercat';break;
case 8 : echo 'gamer/weegee';
};
echo '/index"><img class="r_logo rightalign" src="'.DOKU_TPL.'images/logo'.$rlogo.'.png" alt="'.tpl_getLang('title').'"></a>