UPDATE: I used custom header links and custom header links (icons) to add simple links. I tried the more complex Header submenus and Brand header theme component, but they caused problems and I ultimately decided that they added unnecessary complexity. Moved to done for now but keeping the topic open in case this conversation needs to be revisited in a future website redesign.
See a potential header design here:
https://hub.youthpowercoalition.org/t/redesign-website/508
Options of Adding a Header
https://meta.discourse.org/t/header-submenus/94584
https://meta.discourse.org/t/brand-header-theme-component/77977
https://meta.discourse.org/t/custom-header-links/90588
https://meta.discourse.org/t/custom-header-links-icons/86307
Custom CSS
https://meta.discourse.org/t/header-submenus/94584/100?u=debryc