Q: i don't see photo stream in any of my iphone or ipad or mac, even i enable the photo stream in photos and camera settings

You cannot see My Photo Stream any longer, if you use iCloud Photo Library. And you cannot manage My Photo Stream on iOS8 like you could on iOS7.  The Photo Stream is streaming in the background, if you enable iCloud Photo Library on iOS8 devices and in the Photos for Mac application.  There is no longer a separate My Photo Stream album.  The streamed photos will appear in the "All Photos" album.

If iCloud Photo Library is disabled, you will see again the My Photo Stream album.  But this album is a fake. In iOS8 the Camera Roll and My Photo Stream are no longer separate, so you cannot delete separately from My Photo Stream without deleting from the Camera Roll as well like you could in iOS8.

Use My Photo Stream to stream to devices that do not use iCloud Photo Library, but don't delete from My Photo Stream, even if the stream is shown as an album, unless you want to delete the photos from all devices.