Alphabet is a holding company that trades under GOOG and GOOGL. Alphabet itself doesn't do a whole lot aside from allocate capital to its subsidiary companies.
Aside from Google, Alphabet owns Calico, DeepMind, GV (formerly Google Ventures), CapitalG (formerly Google Capital), X, Google Fiber, Nest Labs, Jigsaw, Sidewalk Labs, Verily (formerly Google Life Sciences - my company) and Waymo. These things are all "Not Google".
Google is everything that's owned/done by Google Inc. This includes Search, Ads, Chrome, Android, Google+, Google Cloud Platform, GSuite (GMail/Docs/Sheets/Slides/etc), and tons of other stuff.
