Tap "Photos" from your iCloud account interface.
First, visit on your PC browser, and sign in with your Apple ID and password.
How to download photos from iCloud to iPhone 6/7/8/Xs/11/12/13: You only need to use the same Apple ID to download the photos from the iCloud website to your PC or Mac, and then use iTunes to transfer them to your iPhone. If you enable iCloud Photos, you can transfer photos from iCloud to iPhone via the site of iCloud. How to Download Pictures from iCloud to iPhone via Wait until the photo download process is successfully completed.
Bonus Tip: Is There an Alternative Backup Software to iCloud?.How to Get Photos from iCloud Photos Stream to iPhone