PHP

get page title wordpress

<?php echo get_the_title(); ?>

wordpress get category page title

//wordpress get category page title 
echo single_cat_title();

wordpress get site title

You are not outputting anything to show. You are only assigning blog name to a variable. You need to echo the content. It should be :

<h1><?php echo get_bloginfo( 'name' ); ?></h1>
Hope this helps :)