Need Help Regarding React Template

We have some confusions regarding React template. If someone can help answering these questions, we will be very thankful.

  1. Can we use custom jQuery & JavaScript files in React template?
  2. Can we use Webpack in React template?
  3. Should we use form validation in React template?
  4. Can we use Formik Validation in React?
  5. Should we use Email Generator in React template or not?