How do I make reusable content blocks for header and footer when using WordPress headless with another front-end?

I’m setting up a WordPress project with Gatsby as frontend, and also using ACF for content. But I wonder how you would setup global content parts like header, footer, or any other kind of content that is being used globally throughout the website? For example both HOME and ABOUT pages need to have their “own” content, but also shares some specific blocks with same content.

I need to be able to edit the content for my header like setting up links to internal pages, be able to edit footer content (like text, an image etc), and for any other global blocks I’m looking for a way to setup them like title, text, maybe an image and so on (ACF control kind of…)

Please help me out!

Thanks