Basic CMS & Pages

Hello,

I am a beginner and I am struggling to use pages on my website.

For this particular website, I use a basic index.php and style.css for my general site-wide content. I would now like to use the “Pages” function in WP to generate dynamic content for +-15 inner pages on the website who all use index.php for site-wide content, and page content for their own dynamic content.

This is what I would like to do, but how to do it in php is quite a different story for me. Does anyone have any tips on how to start?

Where should I point my links on my site-wide content to get the pages displaying properly?

How do I get the page content from the database integrated into the website?

Kind Regards,
Adam