Yeah Phex, flour is flour, but not exactly.
Some wheat flours have more or less protein. The more they have, in general, the better they are for bread. Just a broad generalization.
The softer they are, the less protein they have, the more they are good for cakes and similar products.
And yes, self rising flour contains leavening in the form of baking powder. So one does not have to worry about how to make the stuff rise.
Baking flour, no idea what that is.
Would probably not try to take a flour and make it a self rising one. Would look at the recipe and add what it says.
Just my two cents. Take care.
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