Title field and <title> meta tag?

1

Do all pages have to have the Title field?

I presume the Title field is different from the meta tag?

If so, what’s the point in the Title field?

2

Usually, pages have a title, that’s why there is a default title field.

It’s not the same as the title meta tag (which needs to be present in the head of every web page), but the title of a page is mostly used in (or as part of )the title meta tag, e.g. example from Starterkit:

<title><?= $site->title() ?> | <?= $page->title() ?></title>

(<?= $site->title() ?> | <?= $page->title() ?>)

You might want to check out Kirby’s Starterkit to get an idea of how it all plays together in Kirby (it also has annotations that help to understand a lot of stuff):