Hello, Jayne G. Lewis! Samsung had briefly given up the memory card in the Galaxy S6 series. Then, it brought back the Micro SD card in the Galaxy S7 series. Galaxy S8 / S8 + accepts memory cards with maximum capacities of 256 GB.
If you just want to restore files such as documents, images, videos and music from an external memory card, you can rely on common data recovery tools; otherwise, you can only use the professional Android data recovery tool, which is able to recover messages, contacts, documents, multimedia files and more from the Android device's internal storage.
I think the current Android data recovery tools are not very mature, it is suggested that you do not easily buy any data recovery tool unless it has help you find the missing data.