Hi,
I’m afraid that there is no way to add it through WP admin panel at the moment.
It can be added by hard-coding; insert PHP/HTML code in footer.php file. You should need to do it via child theme. Thus, you should need to create a child theme first (if you don’t have it yet), then copy footer.php file from parent theme, then paste it into child theme.
Open footer.php file of child theme. Then find the following line of code.
echo '<div class="zerif-copyright-box"><a class="zerif-copyright" href="https://themeisle.com/themes/zerif-lite/"'.$attribut_new_tab.' rel="nofollow">Zerif Lite </a>'.__('powered by','zerif-lite').'<a class="zerif-copyright" href="https://www.ads-software.com/"'.$attribut_new_tab.' rel="nofollow"> WordPress</a></div>';
Insert you menu right before the
<div class="zerif-copyright-box">
closing tag.