Title values are not automatically applied to your theme because this will be changing your design, so you have to manually insert them in your themplate:

Files to modify (.tpl or .twig):
/catalog/view/theme/[theme]/template/common/home
/catalog/view/theme/[theme]/template/product/product
/catalog/view/theme/[theme]/template/product/category
/catalog/view/theme/[theme]/template/product/information

Insert these codes for .tpl:
<h1><?php echo $seo_h1; ?></h1>
<h2><?php echo $seo_h2; ?></h2>
<h3><?php echo $seo_h3; ?></h3>

Or these codes for .twig:
<h1>{{ seo_h1 }}</h1>
<h2>{{ seo_h2 }}</h2>
<h3>{{ seo_h3 }}</h3>