Hi @mullexoxo – it sounds like you might be searching for the Image block within the Navigation block, but that won’t be possible, as only specific blocks are available inside that one.
Try adding the Image block outside the Navigation block, but still inside the Header template part – it should come up there. If you’re having trouble inserting a block outside the Navigation block, I’d suggest using the List view to better see the template structure.
The other thing to keep in mind is that if you’re using an eCommerce plugin, it often provide its own method for adding a cart icon into your navigation without needing to do it manually. Folks in the plugin’s support forum should be able to help with that!