Newbie... Need help

Hi all,

I have a second hand coup which I have done a few repairs to and I need some advice...
The coup is a triangle ark, 6' x 3' with a 3' height, the 6' includes a run... It has a perch but no nesting boxes and the floor inside the coup only has half of it with wooden boards.
I am planning on treating it for red mite before getting the chickens...
Underneath the whole coup there are slabs and the chickens will be allowed to have access to the whole of my garden which is surrounded by a 6' wall or fence...
what do I do about the open floor... And the nesting boxes (are they needed)
How many birds do you think I will be able to have??? (I would like bantams)
What do I use in the coup for bedding and what about in the run (which is not covered but I could make it so if needed)
How often do I need to clean out???
I understand about the grit, pellets, oyster shell and corn, but what about our scraps, what can I give them and what will harm them and does it need to be cooked???

Sorry about all the questions, but as I am new to this I hope someone can share experience

Defra should do somthing usefull like stoping battery farms instead of comming up with rubbish like dont feed chickens with kitchen scraps