Paragraphs module decoupled structure
It sounds like you want a compound document, the JSON:API mechanism that provides other referenced entities in a resource (e.g. a "page" content node that references other paragraphs). This is done via adding an include query parameter with a value that refers to a field's relational ID. An inclusion request will add an included array property with the related entity resource objects.

See the docs on Includes in the JSON:API docs for more concrete examples in action. 

Since you mentioned it, ordering included resources isn't possible (IIRC); you might be able to infer order based on the Paragraph field. JSON:API is designed for minimal configuration and maximum adherence to the JSONAPI spec so you're limited to a couple of mechanisms to modify the output of the structured data.