Add the Logo Using the WordPress Customiser (Better part 1).php

<?php 

function my_theme_setup() {
    /**
     * Add support for core custom logo.
     *
     * @link https://codex.wordpress.org/Theme_Logo
     */
    add_theme_support( 'custom-logo', array(
        'height'      => 190,
        'width'       => 128,
        'flex-width'  => true,
        'flex-height' => true,
    ) );
}
add_action( 'after_setup_theme', 'my_theme_setup' );