There are many ways to do affiliate marketing. One way was the kind you learned, posting links and paying for ads. That can get super expensive if your links aren’t converting well! That’s why I recommend that you do “blogging”, e.g. writing articles as you mentioned. If you optimize your content based on search engine requirements (also known as SEO), you’ll rank on page 1 of Google. When someone searches a topic, your article turns up. They read the article, click a link, buy a product, and you make a sale.
Education occurs most often in "real life" by becoming involved and learning the details as time progresses. Although there are several books on the topic, some so-called "how-to" or "silver bullet" books instruct readers to manipulate holes in the Google algorithm, which can quickly become out of date, or suggest strategies no longer endorsed or permitted by advertisers.
Affiliate marketing is commonly confused with referral marketing, as both forms of marketing use third parties to drive sales to the retailer. The two forms of marketing are differentiated, however, in how they drive sales, where affiliate marketing relies purely on financial motivations, while referral marketing relies more on trust and personal relationships.