It’s not at all like that. A 32 gram serving of typical peanut butter has one or two grams of added sugar. Two percent of the rest of it, or two thirds of a gram, are oil and salt. So 29 grams, or more than 90%, is peanuts. What percent of purple Kool-Aid is grape?
To answer the OP’s final question, yes, most of us put peanut butter on bread, and sometimes we make cookies with it, which are delicious in my opinion. Since you have never tasted it, I wonder if you could get a jar of commercial PB sent to you from someplace so you could see how it normally tastes.
The brand we always when I was a kid was Adam’s, which I see was acquired by Smuckers in 1988 (though it looks like they’re now selling peanut butter with both brand names.) That was traditionally peanuts+salt, and so of course you’d have to stir it if it had set for too long and separated. I’m told that people who were used to other brands found this disturbing.
I’d be particularly careful about the roasting. I think you need to get almost all of the water content out of the peanuts before grinding, so rather than a quick browning be sure to roast at a moderate temperature for enough time to get all the water to evaporate out.
Especially good on toast. I also like it on celery. Or sometimes, just on a spoon. 
Yes, on celery is very good, or apples.
But it is like that. The proof of the pudding (or peanut butter, in this case) is in the eating. It looks different, feels different (almost all commercial peanut butter has a consistency nearly identical to shortening) , but most importantly it tastes different.
Indeed there are. There are four main market varieties of peanuts: Runner, Valencia, Spanish, and Virginia. Runners are the most common variety used in peanut butter, with Virginias a distant second. Spanish peanuts are mostly grown for their oil. Valencias and Virginias are the most common “snacking” peanuts.
You could probably make peanut butter out of any of them, realistically, though. This is just they way they do things in the States.