What I’m looking for is the following:
A simpel way of showing 10 pictures - they are all the same width.
In a row under each other from a database or folder.
This in order to make it super easy to change pictures.
And there are 5 different databases or folders.
Have a look at http://www.dukowa.eu/Food.html as an example.
Also
Is there a way to display the latest post from an instagram account on a webpage?
I have no idea how to even start 
So anyone?
Not tried this but.... Instagram Graph API - Instagram Platform - Documentation - Meta for Developers
There should some example already on the forum showing a few ways ,like:
but it really depends on who is doing the uploading and how and to what the server allows. Is this internal use/external use so on.., If the directory cannot be read directly from a browser ( for what evere reason ) then there is php that should be able to lsend back a list.
Again I think examples are around.
A very simple way would be to have a directory on a server with the images and a json file listing them.
But as I say more info on the setup would help someone help you 
It depends on your server or setup, but realistically if you want this to be as easy as possible you can just make a .hype document with normal images, and then just replace the images by uploading new ones onto the server whenever you want with the same name. (A tip would be to uncheck "Automatically optimize when exporting" in the Resources Library so you don't necessarily have to deal with retina images or if Hype changes the naming format).
I haven't tried this but googling for "instagram embed widget" seems to have some solutions that could probably be used in the Inner HTML of a HTML Widget in Hype.