Can I back up a whole S3 bucket or another cloud storage?
It depends on the kind of backup you are looking for.
When it comes to backing up an S3 bucket, you should use "Storage Replication", which allows you to synchronize your bucket to another one (cross-provider).
This means that all your buckets will be mirrored, to another bucket on schedule.
This is not considered a "backup" in the sense that we don't store any archives, instead, it's a 1-to-1 copy of your bucket at a given time.
/as the source storage path.