Great Q&A call. We went down a small rabbit hole around ranking, SEO, etc. Do you know about HubSpot Academy? It's feee and there's a wealth of information on all things inbound marketing. HubSpot provides a really valuable resource.
I have only received certifications on a couple of courses, all free. None around Google specifically. But if looking to learn, I see they have one on your Optimization Score w/ Google. They have another I see on your Google Page. Then for SEO in general, they have a couple of dozen courses. Definitely worth a watch.