Have you tried to create a new React app using
npx create-react-app and then seen this error message in your console of your choice?
npm WARN exec The following package was not found and will be installed: create-react-app
Then you might be wondering what the problem is. It means that the package
create-react-app is not installed, or at least not available from the directory you are in.
However, the message is also saying that it WILL now install the create react app package so that when it completes it’s process and shows you the cursor again it will have installed create-react-app.
Try to create your React app again
At this point you can try again with your original command:
npx create-react-app react-bootstrap-button-example
… and you should find that it creates your React app normally.