What is the difference between running `react-script start` on ec2 and hosting the result of `react-script build` on S3

I want to deploy my react app on public. But I don't know anything about deployment. When I read articles or documents about deployment, they say react-script build command creates bundle file for deployment at dist which is a set of static files. So some static file hosting services like Github pages could serve those htmls. I think it is fully possible that all product code of the client side project via this kind of static file hosting services. Is it right? I mean like is 'running react-script run on an ec2 instance' valid choice for the deployment of react app?