Wait... I don’t have this option. I have ‘add to album’ Winter
are you in the chapter? click start reading, once you're in then the multipage option is just as shown by user KenGoldenTree. if you're on mobile then you need to click the 3 horizontal line in a box near the right corner. a pull-down option will appear and you will see "muilti pages".
Is there a posibility to read in which u only have to scroll down the pages?