Access to fetch at from origin has been blocked by CORS policy SOLVED in React JS

Описание

How to solve the error Access to fetch at 'http://localhost:8000/' from origin 'http://localhost:3000' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled. in react js node js is shown