I have a Mac and poked around at this today. (MacBook Air, running Monterey 12.1 and LO 126.96.36.199.)
I can confirm Marja's report as it applies to Writer.
One of the Mac substitutions for the Home and End keys (which I don't have on my keyboard) are fn+left arrow and fn+right arrow. When I try these in a Calc spreadsheet, they take me to the start and end of the row as described in the Getting Started Guide in the "Cell navigation" section. So the statement specifically with regard to navigation in Calc is actually correct.
However, in Writer, fn+left arrow and fn+right arrow take me to the start and end of the document, as Marja describes (command+up arrow and command+down arrow, the other common Mac substitutions, do the same).
Also confirming ctrl+home and ctrl+end do nothing in Writer.