If you really want to learned Baking I would suggest you invest in two books. They are written for professionals, but these books will correct all of your misunderstandings about baking.
How Baking Works by Paula Figoni This is NOT a recipe book. Rather this is an explanation of the science of ingredients in baking.
Advance Bread and Pastry a Professional Approach by Michel Suas. This is a professional textbook on the proper methods in baking and it includes the science of baking.
Most of the questions you ask are irrelevant.
For instance, the hemisphere you live in
has nothing to do with baking. Rather, the country of Origin is important because the flour protein will vary by country. Canadian flour is very high in protein. English domestic Flour is so low in protein it cannot be used for bread. The milling technology of the flour is different in France, and that effects the flour quality and characteristics. Canada and the United States uses a different grading system for eggs than Europe, so a “large” egg from these counties is equivalent to a medium egg in European countries.
Imperial measurement is not the same as US units.
Most of your questions indicate you just lack fundamental understanding of baking.
I would stay away from YouTube because vast information online is incorrect. If you purchase the two books I mentioned you will see what I mean.