SEO can seem complex but to keep it simpler, you can break SEO into three foundational areas: crawling, indexing, and ranking. Every problem and every SEO factor relates to one of those three areas.
Read Simplify SEO: Crawl, Index, Rank →Does your website use valid HTML code? W3C Markup Validation is a free tool you can use to validate your website's HTML code. If you are using an out-of-the-box WordPress template with a mixture of plugins, chances are there will be validation issues on your website.
Read Valid HTML Code →How many images are needed to load your website? Or JavaScript files? Or CSS files? Or font files? How many bytes do those types of files consume? You can find out by using Chrome's Dev Tools. Before opening a webpage, right click in Chrome and click "Inspect".
Read Measuring Website Resource Files →If you are looking for a different perspective on issues that might be affecting your SEO performance, it is worth checking out the site scan tool in Bing Webmaster Tools. Using Bing Webmaster Tool's Site Scan, you can launch a scan of up to 10K pages on your website.
Read Bing Webmaster Tools: Site Scan →To understand schema, and know how to debug problems, it helps to write out the schema code yourself. That way you can understand how each part of schema works.
Read How to Write Schema Code →