There is 2 ways to go about it. Digital marketing needs to link with a business. Either you run a business or you work for others. Both have great opportunities right now as more people get access to the internet with smartphones today, and more people are open to paying for stuff online.
I would say the process of digital marketing boils down to these few
Ideally, you wanna have the general idea of everything, and then specialise in one or two aspects for a start and be the best at it. For me, I'm great at emails, content and SEO.