You may be wondering what a content mill is. Basically, it is a company that acts as a go-between, matching up writers to clients for various writing projects. The typical type of writing for a content mill is a short article about any number of topics that is search engine optimized and will be posted to a website or blog.
Two of the top content mills are Textbroker and The Content Authority. There are many, many other sites you can find, but a majority of my first income came from Textbroker. You will need to provide a writing sample, which is how your writing skills will be assessed and how your author rating will be determined. Make sure your sample is your very best work, because it directly affects your pay rate.
Before signing up for any site that pays you for writing, do a Google search and make sure there are no scam alerts or other issues with the company. There are many reputable companies, but also some that are not so good, so do your homework before signing up.
Writing for content mills will not get you rich, but it will get you experience and some income while you learn the ropes of online writing and decide how you want to proceed.