All purpose
yes
Yes, you can.
Yes, you can use one part soy flour to four parts wheat flour.
Any recipe for dumplings that require flour of any kind can also use whole wheat flour. Simply substitute the whole wheat flower for the same amount of regular flour in the recipe.
Yes you can use whole wheat flower
No. Whole wheat flour has not been ground as finely as white flour, nor bleached. However, if you use the correct proportions, and add in a little wheat germ, you can get something similar, graham flour.
You could simply use Almond flour or Wheat flour in place of the buckwheat flour.
Teff can be used as a substitute for wheat. If you are making injera bread but teff flour is not available, you can use wheat flour, rice flour, or barley flour.
You use a regular bread recipe and substitute half of the flour with whole wheat flour.
"White flour" is wheat flour, it's just been processed in a slightly different way. It's perfectly fine to use whole wheat flour instead of white flour in a pizza crust.
Same way you use bleached flour.