Using native fetch with Remix

[mashkovtsevlx]

The Problem
My app accepts the file input from the user.
I need to process this file in the client, and send the processed data to backend in chunks asynchronously (in multiple simultaneous fetch requests).
Server has to return the response to the client, which will be then processed by client (asynchronously as well).

I can't use useSubmit and useFetcher for this, so I have to use the native fetch. The only unknown for me here - is how to authenticate native fetch requests.

The questions

1. Is native fetch a correct solution for this problem?
2. If so - how can I authenticate native fetch in the same manner as useSubmit requests are being authenticated?