The previous tennant in my flat has removed part of a door frame in a kitchen cupboard in order to fit in their fridge. It looks a mess so I would like to remove the rest of the frame and cover up the gap with a smooth finish and edge so I can paint over it. How do I go about doing this? I am a complete novice to this but will definately try it myself. Cheers

What is the depth from the brick to the finished painted wall?

If the depth is enough you could cut to size and stick plasterboard to wall and give it a skim.

its about 8mm. I haven't taken off the rest of the frame yet but im guessing it will be roughly the same all around