You can upload images, but not other file types through the image button on the edit bar on your wiki. Data limitations depend on if you're an Ascendant subscriber or not.
There probably is some practical limitation on how much texts fits on a single page, but I've never run into it, nor heard of anyone doing so, and many of my pages contains hundreds if not thousands of lines of content and HTML.
It's probably best to upload files for your campaign somewhere else, and just link to them from your campaign here. OP isn't really set up to be a file server.
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There probably is some practical limitation on how much texts fits on a single page, but I've never run into it, nor heard of anyone doing so, and many of my pages contains hundreds if not thousands of lines of content and HTML.