How To Use The Drive Correctly?

Hi, I’m pretty new at this dual system back up thingy. So I’ve set up in a way that it’s stored on 1 disk. Can I confirm that the other disk automatically mirrors my storage contents?

80% of the storage used are my photographs and photography related stuffs. I’m a photography hobbyist. I find that when accessing the cloud especially viewing photos, it takes quite a while to load. Will changing the ethernet cable to a high-speed one allow it to process faster?

Also, I’m wondering what is the working process for any photographers out there. Can I access this cloud duo like how I would with a portable hard disk? Can the iCloud duo be used as a working hard disk as well? Or should I just strictly treat this as a storage drive.

Appreciate if I can get some answers. Thank you.