SyntaxError: Cannot use import statement outside a module

I am following along Mosh at the beginning of his Redux course when he improts Map from immutable but, unlikely him, I am getting this error SyntaxError: Cannot use import statement outside a module.
This is my code:
import { Map } from ‘immutable’;
let book = Map({ title: ‘Harry Potter’ });
console.log(book)

Googling around hasn’t been very helpful and actually, it made me more confused.

Any tips?