Display field on all pages

Hello, I have a question:
1) How can I create field and display it on all pages? I have contact information in footer and I want to have possibility edit it in admin panel in one place (for example homepage page). When I want to display it in theme, it shows only on homepage. I have to add text to this field on every page. How can I do this?

My code look:

        $meta_boxes[] = [
            'title'      => 'Stopka kontakt',
            'post_types' => 'page',
            'fields'     => [
                    [
                        'name' => 'Stopka kontakt opis',
                        'id'   => 'stopka-kontakt-opis',
                        'type' => 'textarea'
                    ],
                    [
                        'name' => 'Numer telefonu',
                        'id'   => 'stopka-kontakt-telefon',
                        'type' => 'text'
                    ],
                    [
                        'name' => 'Adres email',
                        'id'   => 'stopka-kontakt-email',
                        'type' => 'text'
                    ],
                ],
            ];