[zozbot234]

If you really wanted to reduce Stoicism to "a few takeaways", it's more proper to start from Stoic cosmology, since its ethics directly relates to it. According to Stoics, the universe as we know it is nothing but a manifestation of pure Spirit or Reason, out of which Matter and Force first separated, then the various forces and kinds of matter also became distinct. But everything in the universe is nonetheless ordained according to Reason, and thus is ultimately why we are also told to pursue reason in all of our actions and not let ourselves be affected by damaging 'passions'. It's a rather anti-materialistic philosophy, quite opposed to modern scientism.