You have opened the photo application from Mac , under the previously shared album you are holding shift key and clicking on first photo and then clicking on last to get selected and then trying to share with a person who has been added in your address book .





This method will only created a new shared album in this example the name of album is " some " when you try to share it with others it won't as only photos are shared and not shared albums ( it could be your previously shared albums or the recent one ) , the second person will not receive any notification in the imap account to receive the photo album invitation .
To share photos see these articles https://support.apple.com/en-in/guide/icloud/mm218e61076c/icloud
https://support.apple.com/en-in/guide/icloud/mmc0cd7e99/icloud
https://support.apple.com/en-in/HT202786