You can hide the "page" titles through "Joomla Menu Manager".
Find the item, and disable the page title from the menu item parameters.
check this thread for more info:
forum.joomla.org/viewtopic.php?t=691031
if you can't do it even though you try all different configurations, you can use CSS to hide it. The CSS rule is simply:
h1.page-title { display:none !important;}
FYI: you can put this CSS rule to any CSS file that is being loaded to your website
Regards.