OK, since I'm obviously too bored out of my mind and after uploading over 2200 images I figured I can kill some time by installing Yoast to boost my SEO.

I'm kind of ok with the SEO plugin I used to use but apparently Yoast is the sh!t so I want to put my big boy pants on and make some serious coin.

First up I wanted to know, where in Yoast I can add custom code that's being injected into the header of each generated page? I'm asking this in order to set the robots and author tag (probably Yoast has its own separate options page for it...  ) and also in order to inject the Google Analytics code which should be present on each page as well.

I am running the Google Analytics plugin, so is the injected code redundant or do I still need it on every page?

I'd greatly appreciate some info about this! Thanks in advance.

The YOAST WP SEO is just that, SEO.
To use Google Analytics, you need to install the "Google Analytics for WordPress" by Yoast.