i just created a patreon page. and when i upload my comic chapter 1, it is not view in vertical format like tapastic. how to make it in vertical format, anyone knows?
There isn't a way to change the way Patreon displays images. You will have to stitch the images into a single file if you want it to display in a vertical format.
By attaching a pdf file to your patreon post, you could try this method.