Question about the use of function expressions in the Sleep Debt Calculator exercise

Sorry for the beginner question, I am at the end of the Function section of the Introduction to Javascript lessons, and I am still very confused about how functions work.
So the exercise asks you to create the functions getSleepHours and getActualSleepHours, and in the hint they suggest you this structure:

const getSleepHours = day => {
  ...
};

const getActualSleepHours = () => {
  ...
};

But this way aren’t we actually creating variables named getSleepHours and getActualSleepHours, since the line starts with const? In the previous lesson I understood that the function doesn’t actually have a name when it’s in the form of an expression.
Later on, the exercise asks to “create a variable named actualSleepHours set equal to the getActualSleepHours() function call.”
But isn’t that redundant? We can already recall the variable getActualSleepHours anyway for its value right?

Here is a link to the exercise if needed:
https://www.codecademy.com/paths/web-development/tracks/getting-started-with-javascript/modules/learn-javascript-functions/projects/sleep-debt-calculator

No. They are arrow functions.

Not sure where you read that. The JavaScript Function lesson has an exercise specifically about arrow functions.

No it is not redundant. If you get in the habit of not storing values returned from functions into variables then you will be calling functions multiple times which is not good coding conventions, will make it harder for others to understand your code and most importantly unnecessarily use more processing power as you will keep running the function rather than just run it once.

Thank you for your answer!

I went to read the Mozilla developer network about function:

And they say that in function expression and arrow function when you don’t specify a name for the function it’s an anonymus function.

So bringing back the example of my first post

const getSleepHours = day => {
  ...
};

getSleepHours starts with const, which would make it a variable, and getSleepHours is the name of the variable. But then getSleepHours is actually also the name of the function??? Then it’s not true what they say in MDN that the function doesn’t have a name.

I understood later that the difference of using a variable SleepHours set equal to getSleepHours is that getSleepHours behaves like a function, so you always have to specify parameters between parenthesis, while SleepHours doesn’t need that and retains the value assigned to it.

Still, it’s kinda confusing for me that in a function expression you start with “const” or “let” but you’re not creating a variable.