Redirect user if not specific user - php

Question

I want to protect the configuration page of a backup plugin in wp-admin.
My user ID = 1. If user is other than 1 redirects out of wp-admin.
The backup page is this: http://www.mysite.com.br/wp-admin/options-general.php?page=updraftplus
I wrote this code but I do not have much experience so please forgive me because there must be errors
*I want to put this code in functions.php, I believe it's the right place.
add_filter( 'parse_query', 'redirect_user' );
function redirect_user($query) {
$user_id = get_current_user_id();
if (strlen($user_id) <> 1)
global $pagenow,$post_type;
if (is_admin() && $pagenow=='options-general.php' && $post_type =='page') {
if ($post_type == "updraftplus") {
wp_redirect( home_url() );
}
}
}
}

Answer 1

I think I got the code right:
add_action( 'admin_init', 'redirect_user_backup' );
function redirect_user_backup() {
global $pagenow;
$user_id = get_current_user_id();
if( $pagenow == 'options-general.php' && isset( $_GET['page'] ) && $_GET['page'] == 'updraftplus' ){
if ($user_id <> 1) {
wp_redirect( admin_url( '/index.php' ), 301 );
exit;
}
}
}