https://tagassistant.google.com/
in case if you find that javascript html or css is not compressed then we must have to enable a line in .htaccess. This ususally start with mod_deflate and just uncomment the line.
check in admin that you have any theme for Mobile layout.If yes then enable it
Convert images into webp for next generation
Some website for this are:
https://imagecompressor.11zon.com/en/compress-webp/ https://tinypng.com/
Deffer JS into footer. This setting is available in Admin. Also minify JS and css from admin but dont bundle the js.
After this set production mode
Another thing is remove any unused chat script ang GTM from website.
We can enable critical css from admin but that depends heavily on coding.
MAGENTO 2 RICH SNIPPETS (SCHEMA.ORG STRUCTURED DATA).
You can test the Google Cards & Rich Cards functionality by using this testing tool from Google, just place a link from one of your products and you will see data is structured as Google expects: Google Structured Data Testing Tool
https://www.mgt-commerce.com/blog/what-are-magento-2-rich-snippets/#how-do-rich-snippets-work
Test your structured data
https://developers.google.com/search/docs/appearance/structured-data
