Many are looking for non-medicinal ways to manage ADHD, so I get questions about CBD oil all the time. While there are research-proven treatments for ADHD that don't involved medications, CBD oil isn't one of them. ADDitude Magazine just updated a really good write up of the pros and cons of CBD, and while it's 'natural' it can have specific, and sometimes serious side effects.
When considering which ways you will use to treat ADHD, always think in terms of target symptoms and then fitting the management tool to the specific symptom. As an example, the most effective way to manage distractibility and focus is medications, but you can also use exercise and sleep improvements, too. If you are trying to work on time management and task management, coaching is one of the best options. You can get more information about how this works in my free, downloadable treatment e-book, which you can find on the home page.
For information on the relative effectiveness of various treatments, see this page on effect size.