Gallery with a clear start and end (instead of endless slides)

How can I ensure that the gallery does not slide endlessly? I would like it to be clear what is the first image and what is the last image. I can’t find this anywhere in the settings or in the manuals. It takes the main image and then on the right you do see the second etc. But on the left you also see images and the main image is in the middle. So the gallery keeps on scrolling. I find that inconvenient. For me, the first image (after the main image) is a size chart. My customers must be able to get to the size chart quickly and clearly at all times.