I am also a new Kerbanaut and I can concur with the above, especially Kerbal Engineer Redux. Also, while you are waiting the few days to really get going, I highly recommend you check out Scott Manley's Youtube channel if you haven't found it already. He is literally Mr. KSP.
https://www.youtube.com/channel/UCxzC4EngIsMrPmbm6Nxvb-A
And something I forgot, your best friends in the world, F5, quick save by default, and F9, press and hold for load quicksave by default. These will help save you from Kurphy's Law. Good luck!