Yes, the free plan includes all features for two weeks to give you a full experience. After that, basic stats remain free, but premium features require an upgrade.
Runna doesn't get everything right. It didn't seem good at adjusting your plan based on performance, if it even tries to do that at all. My first few weeks of runs were much too easy, and I had to experiment with manually generating different plans with faster and slower target race times until the zone paces seemed right for me. Would have been great if it adjusted on the fly and I could have kept the same plan.