Hello,
Thank you for using our theme!
WP Rocket plugin comes bundled with our theme and you can use it for free from now.
You can manage cache plugin settings according to plugin docs https://docs.wp-rocket.me/category/1581-starter-guide
You can read about XStore AMP plugin here https://xstore.helpscoutdocs.com/article/111-general-info-amp
AMP version is different from the default mobile version because it’s very simple. So, check and decide if this is suitable for you.
Regards