Oh, you could certainly learn to do SEO yourself. In the same way you can learn to tile a floor or replace your care engine. If you have the time, patience, and passion, then go for it. However, SEO, just like most other skills, takes time to learn to be good at it.
Search engine optimization is a rich mixture of art and science that requires a lot of research and expertise. In the end, an SEO expert will save you time, money, and give you peace of mind that the work has been done correctly.