Here is a good article on adding google analytics to your panel along with JetPack.
This article has several really good sections on how to analyze the statistics once you begin your data collection:
Next, here are a couple of links to the most-used/best analytics plugins.
Be sure to do you due diligence on your analytics plugin provider. These 2 have over a million installations. There are tons of analytic plugins so you have many options.
There are a ton of statistics one can collect about their site and its visitors. One key skill for you to learn is which statistics are reflective of your most profitable visitors vs ones that need a little additional marketing vs marketing to a brand new visitor. For example, if you have a high cart abandonment rate, why? Visitors staying on your site reading, but not engaging with you -- why? The reason that I mention this is as you gather your site statistics, you'll need a comparison. Start looking for sources within your industry/business type that you can begin to reference. Once you have some reference points, both internally and externally, you can put your site statistics into a meaningful context.
Hope this helps.