Canonical - how to get page name

I think I understand that the point of a canonical link is to show search engines the one true page URL.

With this in mind I have written the following code into my ‘head’ snippet:

<link rel="canonical" href="<?= $site->canonical() ?><?= $page->NAME() ?>">

The site canonical is:

… telling the search engine that I want the page to be https and include the www

And then I want to be able to automatically add to the end of this the page NAME, for example:

How would I do this?

Or if I set up my .htaccess file to take visitors to the URL starting with https://www then is the above necessary? Could I then simply use:

<link rel="canonical" href="<?= $page->url() ?>">

because this will include the https and www