Connecting external js file to create-react-app?

Question

JavaScript

Hello, such a question, I need to connect an external js file to my react project, I tried it via index.html, it gives an error Uncaught SyntaxError: Unexpected token '<',

Answer 1

If you collect as a collector, then you can’t insert inline (not exactly).

Answer 2

Uncaught SyntaxError: Unexpected token '<',says that instead of a script, html is loaded for you.
Most likely the path to the script is wrong.
For example, the path is relative and the project is not at the root or the history api is used: in this case, the paths in the application are resolved by the router, and the hard-wired script suffers.