Need help with php in Piano Black theme

I know nothing about php. I can find the call for pages in the header info, but want I want to add to the nav bar are links for my chat and forum, which are not in wordpress. Can anyone give me the modified code to add to the header file? Don’t know where else to ask, as the theme home page is in Japanese.

<li class="<?php if (!is_paged() && is_home()) { ?>current_page_item<?php } else { ?>page_item<?php } ?>"><a href="<?php echo get_settings('home'); ?>/"><?php _e('HOME','piano-black'); ?></a></li>