Content marketing is an offshoot of on-page SEO, but it’s a standalone marketing strategy. Content marketing allows you to share your expertise with the world, typically through written content like a blog. But you can certainly create videos and podcasts if you have the equipment to do so effectively.  Quality matters here, so if you’re not confident in your ability to create high-quality content, consider outsourcing that work to a marketing agency that has the ability and means to create that content.