Use below code
For home page
Full code
<title><?php print get_the_title(); ?></title>
For home page
<title><?php print get_bloginfo( 'name' ); ?></title>
Full code
<?php if(is_front_page()){ ?>
<title><?php print get_bloginfo( 'name' ); ?></title>
<?php } else { ?>
<title><?php print get_the_title(); ?></title>
<?php } ?>