Writing online is one of the most convenient and simple means of generating an online income; and there is also an impressive amount of flexibility when it comes to the choices of topics/niches you can write about. Perhaps the best feature of buiding a career or generating an income online by writing however, is how it can be directly benefited by the passions/interests of the writer in question. If you happen to enjoy writing (or are simply passionate about) informative articles, comedy, or perhaps even DIY tutorials, you could start writing submissions to select websites and start earning money right now.
To get started with earning an income online by writing, all you need to do is perform a web search with the keywords "write for us," and the results should immediately display various different websites and businesses which have programs where freelance or hobbyist writers can be paid per submission:
Another option you have is to search for available freelance writing contracts or jobs on websites such as Fiverr or Freelancer.com. These websites are specialized databasese for freelance work/contracts. You can find some very specific work/contract opportunities by performing category searches within a freelance database, I have provided below some snippets of the broad writing categories provided by Freelancer and Fiverr.coms as well as some example freelance contracts which can be found on Upwork.
The three images above display the broad categoy selections pertaining to freelance writing work available on Fiverr and Freelancer.com, as well as some example contract offers found on Upwork.com. It is quite possible to customize your freelance writing around some qualifications and/or skills that you may have in the real world, such as legal writing or translation. Beware of the possibility that certain freelance contracts may be locked by region or country.
If you are interested in writing more substantial materials, then there are a couple of other directions which you should consider. There are also some opportunities to potentially develop a more advanced writing career online (or perhaps even in person) through some organizations which are open to written submissions. A couple of these organizations include The Hallmark Channel and The Smithsonian Magazine.
One important thing to consider before you start writing online for money however, is where you would be best suited to start. Although many of the websites mentioned above may not have any pre-requisites or credential checks for you to make submissions, some of the more prestigious institutions such as the SmithSonian Magazine and many Freelance contractors will require at least some credentials to justify your submission/work. Although you do not require a college degree in language arts to start taking up freelance writing contracts or making submissions to more demanding websites, having at the least a small portfolio of written materials you have produced (which are preferably although not absolutely required to be relevant to the topic/niche you will be writing about) will always help your chances in acquiring a freelance contract or having a submission accepted.