You can try starting up a blog and writing content and then once you get the website traffic you can monetize the website or blog with Adsense or affiliate products.
You need to write on something you know a lot about and write on a topic that has high paying niches to really earn a decent amount of money.
You'll have to work hard on your blog though to get it earning good money eventually and it won't be overnight but once you write those blog posts they can continue to earn money for you over the years without doing much.