mikesymonds
Hi
Sorry there is no menu item for this type as it is part/item of group. You can copy the URL from browser and use a external url type menu.
To add friends in closed group There is option to send invitation. You can see button invite friend : http://prntscr.com/19mcgrt
Group details tab is important as it show information of group You can set the default tab from Theme designer group options : http://prntscr.com/19mcr4j
If you remove invite friend option you can not add member in the group as you are looking. It will be done by edit the layout file of group
From /component/com_community/templates/jomsocial/layout/groups/miniheader.php
find
<div class="joms-focus__actions--desktop">
<?php if ($isMember) { ?>
<!-- invite friend button -->
<a href="javascript:" class="joms-focus__button--add"
onclick="joms.api.groupInvite('<?php echo $group->id; ?>')">
<?php echo JText::_('COM_COMMUNITY_INVITE_FRIENDS'); ?>
</a>
<?php } elseif(!$isBanned) { ?>
<!-- join button -->
<a href="javascript:" class="joms-focus__button--message"
onclick="joms.api.groupJoin('<?php echo $group->id; ?>')">
<?php echo JText::_('COM_COMMUNITY_GROUPS_JOIN'); ?>
</a>
<?php } ?>
</div>
Group details tab code is in the single.php file.