What do you think is the best option to make money in online fields ?

Your question is seemingly a very big one which I want to believe is coming from a sincere heart that needs tangible answers. We may not have an absolute answer to this question, however, I will contribute the little I can to this timely question.
I start by saying that there are so many businesses or options online to make money, if you will permit me, I like to say that the online space has the biggest opportunities to make money presently.
Money is on every page of the internet but the real issue we are having is that, it's not everybody that are able to see the money on this pages. For example, a thousand and one very creative content creators are passing posts about steemit on their different social media sites weekly without knowing that they can actually earn on this platform if they put some effort or even try to check out the platform.
Many people out there with super graphics designing skills doesn't know that there is a platform like guru.com, freelancer.com, fiverr.com, upwork.com etc, that can fetch then passive income even into the thousands of dollars monthly and even some content writers are not aware of some of those freelancing sites I just mentioned.
However, there are many other ways to make money online like; drop-shipping, blogging, affiliate marketing etc. none of these ways is the best.
I will conclude by saying that the best way or option to make money online is knowing your onions well about what you're doing online because that online business that you are struggling to make $10 a week, some other people that knows what to do will be making $5000.

I am your friend and I hope my answer will be helpful.