Q: I lost my Iphone, I do not have an Apple device right now. How can I see my Icloud photos?

If you only backed it up and did not enable the photo library function you will have to restore the backup to some iOS device to retrieve the photos.

An iPhone backup to iCloud does not result in photos (or anything else) which can be viewed at icloud,com; the backup is only usable for doing a restore to an iOS device or its replacement. The following link has details on how you can use a pc to see that the device was backed up to iCloud -- but it will not allow you to view the contents of the backup: Manage your iCloud storage - Apple Support