To include the entire body, you'd just need to put in a very large number for the Include body in feed. 10 or 20k characters should cover it for most posts unless some of your users write novels
As for including all new posts. There isn't a setting just for that, as what's actually new will depend on the user and when they are looking at the feed. Usually it's around the last 10 topics but you can adjust that to more if you'd like.
