Why is my dough not rising when I use baking powder?

Because baking powder is designed to release carbon dioxide in the presence of moisture and heat. When you add baking powder to a cake recipe the batter does not begin to rise until after you begin to bake it in the oven.

Proving refers to the way a bread dough rises under the influence of yeast. This is an organic process with the yeast organism feeding on the sugar in the flour, multiplying and releasing gas.The gas is captured by the stretchy sheets of gluten in the dough, gluten that has been stretched and spread during the kneading process - that is why bread need time to rise BEFORE baking.

If you want to make a bread using baking powder you need to use a recipe for Baking Powder Bread, or you could make Soda Bread, Scones, or unleavened bread. Sourdough bread can be made without adding any yeast but in that case you must first create a starter by causing the natural yeasts in Rye flour to multiply.

There is no proving or rising time required for baking powder or baking soda breads, that all happens in the oven. They are quick breads. You can have Irish Soda Bread on the table 30 minutes after you begin mixing it.