Error: Cannot find module 'E:\10th semester\oop2(C#)\After_Semester\react6\my-app\demo\node_modules\babel-loader\lib\index.js' Require stack:
Looks like you have missiong dependencies. Open terminal in root of your project and run command npm install. It will fix your issue.
There might be dependencies that are not installed yet. Try checking your package.json file and check if all dependencies are listed there. If not, try running npm install.