Hi there,
I’ve got a header that’s fixed to the sidebar. When I add widgets they don’t appear except in the plus(+) bit of site… How do I make content and widgets appear in header when its a sidebar?
That is called the Header Widget Area and that area is designed for additional contents. If I understand correct, you want to place content above the header that is always on display? If so, you should place your content in the Topbar. Please see https://community.theme.co/kb/customizer-header/ to learn how to set it up.