Hello, is there any app that shows reviews on google search? Like stars and number of review?
Hope you are doing great 
There are several Shopify apps that can show review rating on Google search results. There is an app created by Shopify themselves, here it is: Product Review.
Or you could check Judge.me - the app ranks high on Shopify as well.
I hope this helps. If you feel like my answer is helpful, please mark it as a SOLUTION. Let me know if you have any questions 