A website index is all webpages that a search engine knows about. Indexing, or crawling, is how Google finds all known webpages.
If your web content is not indexed by Google, it cannot appear on a Search Engine Results Page (SERP) when users search via Google. Although search engines use advanced technology to automatically find, crawl, and index your web content, there are extra steps you can take to ensure your content is indexed properly.
The easiest way to see if your website is in the Google index is to search Google for "site:[yourwebsiteURL]". The search results should contain all your web content that you expect to be indexed.
For more advanced insight into how Google has indexed your website, use the Google Search Console.
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