Dynamic content and rewrite URLs

I would suggest the use of the Insert PHP plugin: https://fr.wordpress.org/plugins/insert-php/

You would have to bind the URL path as a $_GET parameter in the .htaccess using RewriteCond/RewriteRule (if you want to keep your URL structure) or use a structure that is something like domain.com?city=New York.

In your WordPress post, you’d be able to include something like:

[insert_php]
echo 'Find wedding services in ' . $_GET['city'];
[/insert_php]

As for the SEO side, make sure you don’t have the same contents on each page as Search Engines give penalties for duplicated contents.