When you opt to implement App Indexing then you may find lots of blogs, documentation out there which may confuse you, in this case, I suggest you to stick to official docs provided by Firebase-Google. Even if you want to use third party to do this, first try follow this documentation because this will give you a clear idea how things are working.
Google will take around 24 hours to index your content. So be patient. You can do testing to make every thing is fine on your side.
First example lets you support HTTP URL of your website to redirect in your App. This will work such as, you have searched a query in the google search, results show one of your website URL, whose app links are present in your app which is already installed. On clicking this URL it will redirect you directly in your App Screen corresponding to that search result. That's it I have discovered for this.
Adding AppIndexing API indexes your content and used in Auto completions in Google search Bar. Lets take example of inShorts Application for each page there is a headline and small description. After reading 2 or 3 headlines, close the application and move to google searchBar.
Try entering headline you just went through, you will get App page suggestion with that Headline as Title. This is different from App suggestions you get while searching for Apps. This happens because you have written AppIndexing API code for this particular page and title is same as you have initialized in