Everyone should be creating content.
If you are building your career build content for what you know.
Life is a journey. Create content about your journey to help the next person on a similar journey.
If you learn something new, build content for what you learned.
Over a period of time, you will have a wealth of content.
The secret is to start small. Create micro-content.
Rather than writing a blog, or a long explanation, simply write a paragraph about one idea.
Eventually, you can put these together into bigger pieces.
By starting small you can start. Think of it as creating a collection of your nuggets of wisdom and knowledge.