Fortnite instant building on M and K?

I switched to mouse and keyboard "new". I wanted to ask if there's the option that if I e.g. C for a bottom press that I don't have to confirm that but that it builds directly on C.

So now it's like this for me:

I press C (floor) it selects floor.

Then I have to confirm with the left mouse button.

Is that possible without the confirmation

No, I do not think so

but it's better that way. You will still notice.

That's not possible.