Excel shortcuts on Chromebook

Hi,

I am struggling to figure out shortcuts in Excel on my Chromebook.

The basic CTRL+ C,Z, etc work but I don't know how to make the F functions to work.

I got a keyboard but it's reacting in excel.

I really need them and don't want to get another laptop. I've browsed all over the internet and forums for help, can't figure it out.

I am paying for the whole Office package so would be great to have a full version of it.

HELP PLEASE!

Thank you very much in advance.

S