No apology necessary, it can be a little confusing if you're not familiar with WordPress and WordPress.com. Basically, Jetpack is a plugin made for self-hosted WordPress installs to help those blogs get some of the nifty features that WordPress.com has built-in.
Before you go any further, you should make sure you understand this:
If you have a self-hosted WordPress install for one of your blogs, you can go to Plugins → Add New in your blog dashboard to search for Jetpack and install it. You can also find out more about Jetpack at http://jetpack.me/
Now, having said that, this is a WordPress.com forum—and you don't need Jetpack for a WordPress.com blog.
If I cannot find the CSS edit link how can I add the code for the answer to #2?
In that case, you can either opt to edit the theme's style.css file directly (not recommended) or make a child theme and add the styles there. To get help with either of those things, head over to http://wordpress.org/support/