Viewing backup data
Can backup data in cloud be viewed on your phone?
There isn't any way to view the contents of an iCloud backup either on an iPhone or at iCloud.com.
However, data synced to iCloud can be viewed in either place. On the iPhone it is viewed via the related apps (e.g., the Photos app, Contacts app, Notes app, Files app etc). If you try to access www.icloud.com from Safari on an iPhone you would need to hold down the semi-circular refresh icon in the menu bar until you get the option to "Request Desktop Site" -- but the results will not be good as www.icloud.com does not have a mobile version of the site.