If you’re passionate about something then write about it.
This money-making idea will likely be a long-term project requiring sustained effort to create a continued stream of valuable content. For this reason, don’t even attempt it unless you’re actually keen and knowledgeable about a particular topic.
After you’ve established your authority and readership, you’ll be able to monetise your contribution. This can be achieved through advertising, referrals, endorsements, books, speaking roles, and many other avenues.
You could even blog about how to make money blogging….