Recover all my photos on iCloud
Recover all my photos and videos on iCloud
iPhone 6s, iOS 12
Sign in with Apple ID and password of an iPhone from a web browser at www.icloud.com , open photos section and recover deleted photos / videos as explained in the article https://support.apple.com/guide/icloud/delete-and-recover-photos-and-videos-mm08b49040b5/1.0/icloud/1.0
The second method is you can directly recover photos / videos from an iPhone https://support.apple.com/en-in/HT205856