I have a large spreadsheet with 15346 rows

I enter a formula in B2, and want to copy it to B3:B15346. (I don't want a copy of the value in B2, I want an adjusted formula in each cell)

Is there a way to enter the range from the keyboard instead of by mouse or arrow/pgdown scrolling down, missing the target, scrolling up etc.

I just want to enter "copy(B2,B3:B15346)" or something to that effect.

I'm using libreoffice, but I hope there exists a generic solution.

Edit: The formula in question for cell D2 is `=LOOKUP($B2;$'hex rgb'.$A$2:$B$24712)`

D3 should then be `=LOOKUP($B3;$'hex rgb'.$A$2:$B$24712)`