If she has iCloud Photos turned on, the photos on the device are the same as on iCloud, with the possible exception that some of them may be space-saving optimized versions if she hs that option turned on. She can view them in the Photos app on an iOS device. She can also login to icloud.com and go to the Photos app there. See: https://support.apple.com/en-us/HT204264
If she didn't have iCloud Photos turned on but does have an iCloud backup, she can use the backup to restore the entire phone (not just the photos) or setup another from iCloud but she cannot otherwise view the contents of the backup. https://support.apple.com/kb/ph12521