How do I control the header space in non-front pages in Twenty Seventeen?

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You can target several of the header elements using CSS. I’d use the site-branding like so:

.site-branding {
  min-height: 50vh;
}

This would set the minimum height of the element to 50% of the viewport height.

You can add this to your child theme’s style.css or via the customizer if you’re running a WordPress version greater than 4.7.