How to migrate from old theme?

I am trying out the Viral theme for a client of mine who needs to migrate from an old, non-responsive theme. This will mean a lot of manual customization of the new Viral theme. I’m hoping I can get some general advice about that; about this specific question to start.

When I activated the Viral theme, and pointed it to a new static homepage, I get some content that was carried over, but am not sure where it is in Viral, and how to modify it: here’s the URL:
dev.steadystate.org/

These look like the navigation pages from the old site, but I’m not finding where they are in Viral. Any suggestions?

Thanks,
Rick Casey