Picture posting is enabled for all :)
a load of old bricks plonked on top of each other (no mortar) with an old window shoved on top.
If you put cut to shape cardboard inside, it will give some protection and warmth, especially if you keep the wet out.
look on the WIKI tab along the top tabs
welcome to the site, 18s..sounds like you have a plan, try it and see, if it doesn't work, try something different