If you’re new to internet marketing and wish to get online as quickly and inexpensively as possible you can start with a social media platform like Facebook - you can create a business Facebook page in less than an hour. However, if you want more control over your online presence, a customized website is more appropriate. Ideally you should have both a website and a social media presence, with each linking to the other.
Creating high quality content takes a significant amount of at least one of the following: time, effort, expertise, and talent/skill. Content should be factually accurate, clearly written, and comprehensive. So, for example, if you describe your page as a recipe, provide a complete recipe that is easy to follow, rather than just a set of ingredients or a basic description of the dish.
The SEO starter guide describes much of what your SEO will do for you. Although you don't need to know this guide well yourself if you're hiring a professional to do the work for you, it is useful to be familiar with these techniques, so that you can be aware if an SEO wants to use a technique that is not recommended or, worse, strongly discouraged.