As stated above, it covers just the basic and there is nothing more basic to SEO than getting your content indexed by Google.
Here we will go through a a brief summary of the information included in the guide.
What does the Guide contain?
HTTP status codes: Make sure that you are using a meaningful status code to tell Googlebot whether a page needs to be crawled or indexed, or whether a page has been moved to a new URL.
Lazy-loading: To save bandwidth and to improve improve the performance, it is recommended to use lazy-loading to only load images when the user is just about to see them.
You can also get the complete JavaScrip SEO basics guide here.