Not saying you should change it if it's working, and I don't have a ready-made tutorial, but assuming you only need to serve static files I would:

  (1) upload the files to an S3 bucket (GCS or Cloudflare R2 may also work, haven't tried);
  (2) point Cloudflare at the bucket via their Cloud Connector;
  (3) turn on Cloudflare Access.