How to organize photos in an album

For shared albums it will depend on your system version.

If you upgrade your Mac to macOS 12 or 13, you can sort Shared albums by the date added or the date taken using the command "View > Sort ..." while viewing the shared album. This is a new feature on the most recent system versions not possible on the older system versions, because the in the older system versions the date has not been available in shared albums. On older system versions the shared albums jhave been streams of photos, always sorted by the date the photo has been added. This has made sense, becaus ethe Shared albums have been intended to to be used as a chat with photos - we drop a photo onto the Shared album, there recipients add a comment to it, then reply by adding a photo od their own, we comment on the new photo, add another photo, etc. When we change the order of the photos in the stream, the discussion would no longer make sense, as the comments would be rearranged as well. Now, tha t the Messenges app is allowing us to to have a chat with photos, we need no longer to use shared Albums to have a chat with photos, and apple has added the soring option to the Shared albums.

In an album you can simply drag the images to the order you prefer. This option I not available in a Smart Album.

Here are the various portion options in the different views/albums in a Photos library:

Correct.