How to add custom theme settings to WordPress

wp_theme_settings.php

<?php
add_action('admin_menu', function () {
    add_theme_page('Customizer', 'Customizer', 'edit_theme_options', 'customize.php');
});


add_action('customize_register', function ($customizer) {
    $customizer->add_section(
        'custom_setting',
        array(
            'title' => 'Custom Settings',
            'description' => 'Description',
            'priority' => 11,
        )
	);
	$customizer->add_setting(
		'company-phone',
		array('default' => '000000000000')
	);
	$customizer->add_control(
		'company-phone',
		array(
			'label' => 'Company phone',
			'section' => 'custom_setting',
			'type' => 'text',
		)
	);
	
	$customizer->add_setting(
		'company-email',
		array('default' => '[email protected]')
	);
	$customizer->add_control(
		'company-email',
		array(
			'label' => 'Company email',
			'section' => 'custom_setting',
			'type' => 'text',
		)
	);

	$customizer->add_setting(
		'company-address',
		array('default' => 'Somewhere in Ukraine')
	);
	$customizer->add_control(
		'company-address',
		array(
			'label' => 'Company address',
			'section' => 'custom_setting',
			'type' => 'text',
		)
	);


});

//Insert into page
get_theme_mod('company-address')