Using Create React App with ASP.NET Core

Make sure you have already set ASP.NET Core app (Getting Started) and React.js app (Getting Started)

To use ASP.NET Core API from React.js app add option proxy to package.json

...
"proxy":"http://localhost:5000"
...

This option allow to proxy requests starts with /api to your API server (ASP.NET Core app).

More info about proxy option Proxying API Requests in Development

Start your apps

dotnet run
npm start

Full example of this approach AspNetCoreDemoApp