Improve our Digital Marketing

A colleague and I run an online course, 3 times per year and we typically get customers via Google/Google Ads. We're a small operation, selling one product and neither of us have a background in digital marketing. We want to increase conversions and drive more traffic. I suspect that there's significant improvements to be made in all areas of our marketing (site copy, ad copy, SEO, Google Ads use, tracking, branding, UX/site quality, mailouts etc.). We are looking for an experienced digital marketing specialist to help us increase our sales.