Nootriment is another supplement review website. They write content for targeted keywords and use affiliate links everywhere.
In affiliate marketing, you can either be a business called merchant, a commission-based platform or network called affiliate network or an affiliate or publisher. For example, I am an affiliate of WP Rocket (merchant) which uses ShareASale (an affiliate network) to make sales.

In the case of promoting consumer products, like tools, books, toys and household items, the biggest affiliate network, by far, is Amazon. Their Amazon Associates affiliate program lets you promote any item that is sold on their platform.
Even if you opt for an affiliate marketing network, it does not mean you cannot find additional qualified affiliates on your own. It is all about building relationships. Affiliates will only want to promote the products and services of brands they trust. After all, they are putting their name and reputation on the line. Do they already have a platform, such as a blog or a website, with quality content? Are they authentic when communicating with their audience online? Have they mastered the art of show and not tell, meaning they are great storytellers that will draw customers in and persuade them to buy? How much traffic does their blog or website generate? The more traffic, the higher the potential for sales. Is their online presence professional, and does it align with your brand position? Do they have a large or engaged social media following? Is the affiliate ranking high for search terms related to your products or services?