So I have my html twine file saved in a zip folder along with the pictures for said branching narrative game. But when I open up the Html, even though the files are in the zip folder, the pictures don't show up in game. Any suggestions pls? 

I recommend opening your browser console to see what kind of errors are showing. Make sure you read through here to learn about common issues people run into: https://itch.io/docs/creators/html5#common-pitfalls