Incorrect FCC lesson on var/let/const or me misunderstanding>

[liv_lilit]

The Explore Differences Between the var and let Keywords lesson (https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/basic-javascript/explore-differences-between-the-var-and-let-keywords)
says, regarding let:
" when you use let , a variable with the same name can only be declared once." My understanding from other sites is that this is actually the behavior of const, and let is the more flexible of the two. Am I wrong, or is the lesson?

The next lesson says, of const " variables declared using const are read-only. They are a constant value, which means that once a variable is assigned with const , it cannot be reassigned".

Are these two statements not equivalent?

[JeremyLT]

Not quite the same thing.

Permitted:

var myVar = 2;
var myVar = 3;

Not:

let myVar = 2;
let myVar = 3;

Permitted:

let myVar = 2;
myVar = 3;

Not:

const myVar = 2;
myVar = 3;

[liv_lilit]

That is a very helpful explanation- I was confused about the difference between declaring and assigning a variable. Thank you!