I have the book you are reading. I have to say it is not one of my favorite.... I won't go into why it isn't because I don't want to turn your thread into discussion of the book itself.
I have to say you are WAY ahead of yourself, especially if you never developed your film. I'll go as far as to say all that is really unnecessary at this point. Today's film are so forgiving, if you can get the exposure reasonably close and develop it normally, you can get a decent image printed. My suggestion is to ignore that book for now for it will make what's easy very VERY complicated.
Since you asked though, I will share my experience.
I have 3 Nikon F-100. I never carry all 3 and label N, N-1, and N+1 as Mr. B suggests. Why? Because I find it unnecessary for my photography. For THAT much of adjustment, I can easily do it at printing time by using different filters. What I do is, if I encounter extreme situations, I expose the entire roll at N, N-1, or N+1 and develop it accordingly. Realistically, I've never been in a situation where I needed all 3 at the same time. Most of the time, I just expose it as normal and develop it normally.
Snow and backlighting condition require special handling. So as dark subject with dark background. It has a lot to do with proper exposure in a situation where in-camera light meters are likely very confused. What you said is called bracketing. It is a good idea but you'll learn how to deal with it as you study photography. It's not as difficult as it sounds....
Yes, if you develop your roll in certain way, you have committed your decision onto that film. But.... think about this too. Your film can record a huge range of brightness. If you error your metering somewhat, it will still record it. You might have to struggle a little when you print but you don't have to have a perfect negative to print your image. If you can get it reasonably close, that's all you need a lot of the time.
There are times you need to be precise. Then you need to do a lot of what Mr. B says. But ahead of that, you need to know how to process your film correctly, and ahead of that, you need to know how to expose your film correctly. Ahead of that, you need to recognize adverse conditions and know what technique to deploy to meter the scene. This is why I said you are way ahead of yourself....
There is a book called "Photography". It is written by Upton and London. (I think) It explains a lot of more applicable topic than the book you are reading. I think that'll be a better book to read.