There are so many books out there but I have ythios idea there are a lot of sites to learn on for free here is one.
baking911
Baking 911 site is no longer free. She "upgraded" her website and now charges.
I have both Nick's "How to Bake" and "Cooking with Julia", and as a pastry chef, I don't feel either are for a "beginner".
I recently reviewed a new release from the CIA, their cookbook, "The Culinary Institute of America Cookbook". It is quite a large book, but has everything from appy's to desserts as well as breakfast items, brunch, drinks from breakfast to cocktails, etc. Quite a complete book. What held my interest in it, however, is that with each section, there are directions and the why's and why not's of how to make and what to expect, of each. For example, pancakes....there is an entire page that explains pancakes alone....what to do with the flour and why, then addresses the wet ingredients, then the combining of both, prepping the griddle, adding the batter to the griddle, etc., up to the time of eating them! Very complete, very clear and consise explanations. Then a nice collection of recipes for pancakes follows. The entire book is like this.
Oh, and PICTURES!!! Lots and lots of COLOR pictures!!! (Just counted, 24 pages of color pix per chapter!) You can probably preview the book on Amazon???