Reply To: my header content does not look good on mobile

[Tom]

You may have to reduce your site title text on mobile:

@media (max-width:768px) {
      .main-title {
            font-size: 30px;
      }
}

As for breacrumbs, I would use the WordPress SEO by Yoast breadcrumbs.

Then place this in the “After Header” hook in GP Hooks: https://gist.github.com/generatepress/14b3e8a93175f11d9545

Let me know 🙂