Site Flipping Noob

What's the best way to analyze my page 1 competition?

I have an idea for a review site that has 10 or so product categories, and 10 products in each category.

Considering SEO, do I have a better chance of ranking if I make an individual site for each category instead of creating a one stop shop?

Looking for training resources on starting from scratch.

silo and micro sites gets much ranking in google