Creating a successful website requires you to have good skills, such as:
1. market research.
If you choose the wrong market, your site is guaranteed to fail.
2. keyword research.
3. technical setup of the site.
4. Design and branding.
5. Content creation.
It's not as simple as just writing about a topic.
6. Hiring and Outsourcing
You don't want to do all the work yourself forever.
7. Monetization. 
8. Analytics and tracking.
You need to set up the right tracking tools to keep track of the growth of your business and understand which areas need your attention and attention.