Flour is the main ingredient in muffins.
Wholemeal flour is much more suitable for muffins
Certainly, white all purpose flour will work in muffins. Although they might turn out to be cupcakes, rather than muffins.
Yes, if you use corn flour to make them.
I would not. Yorkshire Pudding is simple to make, but corn flour would REALLY change the texture and flavor. Stick with wheat flour.
Muffins can be made with white flour, unbleached white flour, whole wheat pastry flour, spelt flour, or a combination of several types of flour. Muffins can be made with self-rising flour if the amount of baking powder, soda, and salt in the recipe is adjusted.
as long as you DON'T use yeast
not really because they'd turn out like muffins
you need all-purpose flour to make a cake. - not bread flour- that is only for bread!
yes
yes
Self-raising flour already has baking powder and salt added to it in the packaging process. It's really just included for your convenience, and you can find plenty of muffin recipes that let you add your own baking powder so you don't have to buy self-raising flour specifically to make muffins.