Hi Marguarita,
Thanks so much for using Apple Support Communities.
We're glad you reached out asking this question before deleting any photos.
When you use the photo albums, it's not duplicating photos on your devices. It's just a way to help you organize and find the photos you want to view easier. So if you deleted the photo from the photo library, it would also delete it from the album.
You can learn more about Use photo albums in Photos on iPad - Apple Support by clicking this link.
Let us know if you have further questions.
Take care!