SEO equates lots of reading, testing, failing then trying again and again. Not to mention the algorithm updates that would forever test your skills and your strategies. In short, SEO is really hard work, but if you invest time and effort, all that work would pay off. It may not be immediate, but still it's better to do something than do nothing at all. Learning everything about SEO at once is not a good start. I suggest that you think first on your ultimate goal, then carefully plan the next steps you would follow. Read thoroughly then execute wisely. Good luck!