First off, thanks for helping me to see that sometimes I would be better going to w3.org versus using MDN - lots lore detail and examples there!!
It seems like there is a lot of overlap with new elements in HTML5 and older ones.
But after reading all of the w3.org link you provided, it seems like a good way to semantically structure web pages would be…
<header>
<h1>branding</h1>
<nav></nav>
</header>
<main>
<h2>content title</h2>
<p>main content here...</p>
<section>Or some content here...</section>
<section>And then some more content here...</section>
</main>
<footer>
</footer>
Does that sound correct?