If you are using a free blog hosting service instead of your own domain name, you must provide high quality content with a limited number of relevant links or risk being shut down. If you are only interested in writing short, quick product reviews in order to earn money, you will need to host your own blog. Be warned that low-content, high-link blogs are a less reliable, though lower effort, way to earn money.
If you want to be successful and really grow the ways you are making money from a blog, then you may want to look into buying ebooks and/or courses that will teach you exactly what to do, so that you can minimize the amount of blogging mistakes you make and learn how to run a successful blogging business from the very beginning. Plus, there are many blogging secrets that you just can't find by searching the internet. So, by taking a course or reading an ebook, you will learn exactly what you have to work on.