Blogger and WordPress (dotcom hosted) are both free and easy to use. Blogger is more "idiot proof" but WordPress is more customisable.
So long as you don't intend to sell anything, then you can keep your identity secret. If you do intend to sell anything... remember the rules about sole traders and distance selling regs.
Making money depends entirely on your skillset. And your time.
You don't need a lot of knowledge. You do need to be able to write about your chosen topic on a regular basis.
As Tee2072 said: you can absolutely do it! Anyone can do it. What we can't all do is generate readership. But we can try! ;) And the more times you try, the more likely you are to succeed. :)