Add custom logo to WordPress them

Open “functions.php” of your theme and write below code.

if (!function_exists('hs_setup')) :
    function hs_setup()
    {
        add_theme_support(
            'custom-logo',
            array(
                'height' => 300,
                'width' => 250,
                'flex-width' => true,
                'flex-height' => true,
                'unlink-homepage-logo' => true,
            )
        );
    }
    add_action('after_setup_theme', 'hs_setup');
endif;